diff --git a/e2e/__screenshots__/vendors/vendors.visual.spec.ts/vendor-add.png b/e2e/__screenshots__/vendors/vendors.visual.spec.ts/vendor-add.png
index 6e091c72..d39596dc 100644
Binary files a/e2e/__screenshots__/vendors/vendors.visual.spec.ts/vendor-add.png and b/e2e/__screenshots__/vendors/vendors.visual.spec.ts/vendor-add.png differ
diff --git a/e2e/__screenshots__/vendors/vendors.visual.spec.ts/vendor-edit.png b/e2e/__screenshots__/vendors/vendors.visual.spec.ts/vendor-edit.png
index a80af4db..93fd2ef9 100644
Binary files a/e2e/__screenshots__/vendors/vendors.visual.spec.ts/vendor-edit.png and b/e2e/__screenshots__/vendors/vendors.visual.spec.ts/vendor-edit.png differ
diff --git a/src/app/(protected)/vendors/_components/use-vendor-roster-form.ts b/src/app/(protected)/vendors/_components/use-vendor-roster-form.ts
index 82ae4333..ea04d62d 100644
--- a/src/app/(protected)/vendors/_components/use-vendor-roster-form.ts
+++ b/src/app/(protected)/vendors/_components/use-vendor-roster-form.ts
@@ -97,6 +97,7 @@ export interface VendorRosterForm {
   selectedCompanyId: string | number | null;
   selectCompany: (company: VendorFacetCompany | null) => Promise<void>;
   clearSelectedCompany: (nextName?: string) => void;
+  setTechnicianActive: (index: number, isActive: boolean) => void;
   resetForm: () => void;
 }
 
@@ -133,7 +134,7 @@ export function useVendorRosterForm({
     values: mode === "update" && routeRoster ? toFormValues(routeRoster) : undefined,
     mode: "onChange",
   });
-  const { control, handleSubmit, reset, formState } = form;
+  const { control, handleSubmit, reset, setValue, formState } = form;
   // react-hook-form exposes formState through a Proxy that only tracks properties read during
   // render. Reading dirtyFields inside the submit callback would not subscribe and would come
   // back empty, so it is resolved here on every render.
@@ -163,6 +164,16 @@ export function useVendorRosterForm({
     clearConflict();
   }, [clearConflict, createDefaults, reset, resetSelection]);
 
+  const setTechnicianActive = useCallback(
+    (index: number, isActive: boolean) => {
+      setValue(`technicians.${index}.isActive`, isActive, {
+        shouldDirty: true,
+        shouldValidate: true,
+      });
+    },
+    [setValue],
+  );
+
   const submit = (formValues: VendorCompanyRosterFormValues) => {
     setConflict(null);
     const values = withoutBlankNewTechnicians(formValues);
@@ -228,6 +239,7 @@ export function useVendorRosterForm({
     selectedCompanyId: selection.selectedCompanyId,
     selectCompany: selection.selectCompany,
     clearSelectedCompany: selection.clearSelectedCompany,
+    setTechnicianActive,
     resetForm,
   };
 }
diff --git a/src/app/(protected)/vendors/_components/use-vendor-roster-resolver.ts b/src/app/(protected)/vendors/_components/use-vendor-roster-resolver.ts
index 12e1810a..864bdb4a 100644
--- a/src/app/(protected)/vendors/_components/use-vendor-roster-resolver.ts
+++ b/src/app/(protected)/vendors/_components/use-vendor-roster-resolver.ts
@@ -8,19 +8,35 @@ import {
 import { getSingleStatusOnlyChange } from "@/domain/vendors/use-cases/use-save-vendor-company-roster";
 import type { VendorCompanyRoster } from "@/domain/vendors/types/vendor";
 
+function withoutTechnicianStubs(
+  values: VendorCompanyRosterFormValues,
+): VendorCompanyRosterFormValues {
+  return {
+    ...values,
+    technicians: values.technicians.filter((technician) => {
+      if (technician === null || typeof technician !== "object" || Array.isArray(technician)) {
+        return true;
+      }
+      const candidate = technician as unknown as Record<string, unknown>;
+      const keys = Object.keys(candidate);
+      const isGeneratedStatusStub =
+        keys.length === 1 && keys[0] === "isActive" && typeof candidate.isActive === "boolean";
+      return !isGeneratedStatusStub;
+    }),
+  };
+}
+
 export function useVendorRosterResolver(
   routeRoster: VendorCompanyRoster | undefined,
 ): Resolver<VendorCompanyRosterFormValues> {
   const strictResolver = useMemo(() => zodResolver(vendorCompanyRosterSchema), []);
   return useMemo<Resolver<VendorCompanyRosterFormValues>>(
     () => async (values, context, options) => {
-      if (
-        routeRoster &&
-        getSingleStatusOnlyChange(routeRoster, values as VendorCompanyRosterFormValues)
-      ) {
-        return { values, errors: {} };
+      const normalizedValues = withoutTechnicianStubs(values);
+      if (routeRoster && getSingleStatusOnlyChange(routeRoster, normalizedValues)) {
+        return { values: normalizedValues, errors: {} };
       }
-      return strictResolver(values, context, options);
+      return strictResolver(normalizedValues, context, options);
     },
     [routeRoster, strictResolver],
   );
diff --git a/src/app/(protected)/vendors/_components/vendor-detail-drawer.tsx b/src/app/(protected)/vendors/_components/vendor-detail-drawer.tsx
index 62d65f15..52b328be 100644
--- a/src/app/(protected)/vendors/_components/vendor-detail-drawer.tsx
+++ b/src/app/(protected)/vendors/_components/vendor-detail-drawer.tsx
@@ -1,5 +1,5 @@
 import { useEffect, useState, type ReactNode } from "react";
-import { Controller, useWatch } from "react-hook-form";
+import { useWatch } from "react-hook-form";
 import CloseIcon from "@mui/icons-material/Close";
 import EditOutlinedIcon from "@mui/icons-material/EditOutlined";
 import LaunchIcon from "@mui/icons-material/Launch";
@@ -211,7 +211,7 @@ function DrawerBody({
           <Divider />
           <Box>
             <SectionTitle>Notes</SectionTitle>
-            <Text variant="description" sx={{ whiteSpace: "pre-wrap" }}>
+            <Text variant="description" sx={{ overflowWrap: "anywhere", whiteSpace: "pre-wrap" }}>
               {roster.notes}
             </Text>
           </Box>
@@ -240,6 +240,32 @@ function DrawerActions({ onEdit }: { onEdit: () => void }) {
   );
 }
 
+function TechnicianStatusControl({
+  isActive,
+  persistedIsActive,
+  onRequestDeactivation,
+  onChange,
+}: {
+  isActive: boolean;
+  persistedIsActive: boolean;
+  onRequestDeactivation: () => void;
+  onChange: (checked: boolean) => void;
+}) {
+  return (
+    <Stack direction="row" spacing={1} sx={{ alignItems: "center" }}>
+      <Text variant="description">{isActive ? "Active" : "Inactive"}</Text>
+      <Switch
+        checked={isActive}
+        slotProps={{ input: { "aria-label": "Active status" } }}
+        onChange={(_event, checked) => {
+          if (persistedIsActive && !checked) onRequestDeactivation();
+          else onChange(checked);
+        }}
+      />
+    </Stack>
+  );
+}
+
 function DrawerEditor({
   vendor,
   onClose,
@@ -312,22 +338,11 @@ function DrawerEditor({
                   Total Jobs
                 </Text>
               </Box>
-              <Controller
-                control={form.control}
-                name={`technicians.${selectedIndex}.isActive`}
-                render={({ field }) => (
-                  <Stack direction="row" spacing={1} sx={{ alignItems: "center" }}>
-                    <Text variant="description">{field.value ? "Active" : "Inactive"}</Text>
-                    <Switch
-                      checked={Boolean(field.value)}
-                      slotProps={{ input: { "aria-label": "Active status" } }}
-                      onChange={(_event, checked) => {
-                        if (persistedIsActive && !checked) onRequestDeactivation(vendor);
-                        else field.onChange(checked);
-                      }}
-                    />
-                  </Stack>
-                )}
+              <TechnicianStatusControl
+                isActive={Boolean(technicians[selectedIndex]?.isActive)}
+                persistedIsActive={persistedIsActive}
+                onRequestDeactivation={() => onRequestDeactivation(vendor)}
+                onChange={(checked) => form.setTechnicianActive(selectedIndex, checked)}
               />
             </Stack>
           </>
@@ -341,7 +356,7 @@ function DrawerEditor({
         <Button onClick={onClose} disabled={form.isSaving}>
           Cancel
         </Button>
-        <Button type="submit" variant="contained" disabled={form.isSaving || !form.isValid}>
+        <Button type="submit" variant="contained" disabled={form.isSaving}>
           {form.isSaving ? "Saving..." : "Save changes"}
         </Button>
       </Stack>
diff --git a/src/app/(protected)/vendors/_components/vendor-roster-form-fields.tsx b/src/app/(protected)/vendors/_components/vendor-roster-form-fields.tsx
index 93a10fd9..df32ae32 100644
--- a/src/app/(protected)/vendors/_components/vendor-roster-form-fields.tsx
+++ b/src/app/(protected)/vendors/_components/vendor-roster-form-fields.tsx
@@ -1,4 +1,10 @@
-import { Controller, useFieldArray, type Control, type FieldErrors } from "react-hook-form";
+import {
+  Controller,
+  useFieldArray,
+  useWatch,
+  type Control,
+  type FieldErrors,
+} from "react-hook-form";
 import AddIcon from "@mui/icons-material/Add";
 import DeleteOutlineIcon from "@mui/icons-material/DeleteOutlined";
 import {
@@ -16,8 +22,11 @@ import {
 } from "@mui/material";
 import { VendorTradeSpecialtiesField } from "./vendor-trade-specialties-field";
 import { formatNorthAmericanPhone } from "@/lib/format/na-phone";
-import type { VendorCompanyRosterFormValues } from "@/domain/vendors/schemas/vendor-roster-schema";
-import type { RosterTechnicianValues } from "@/domain/vendors/schemas/vendor-roster-schema";
+import {
+  VENDOR_NOTES_MAX_LENGTH,
+  type RosterTechnicianValues,
+  type VendorCompanyRosterFormValues,
+} from "@/domain/vendors/schemas/vendor-roster-schema";
 import type { VendorFacetCompany } from "@/domain/vendors/types/vendor";
 
 interface VendorRosterFormFieldsProps {
@@ -121,6 +130,8 @@ function CompanyFields({
   onSelectCompany,
   onClearSelectedCompany,
 }: VendorRosterFormFieldsProps) {
+  const notes = useWatch({ control, name: "notes" }) ?? "";
+
   return (
     <Box>
       <Stack spacing={2}>
@@ -222,6 +233,19 @@ function CompanyFields({
               multiline
               minRows={2}
               fullWidth
+              error={Boolean(errors.notes)}
+              helperText={`${notes.length}/${VENDOR_NOTES_MAX_LENGTH} characters · ${
+                errors.notes?.message ?? `Maximum ${VENDOR_NOTES_MAX_LENGTH} characters`
+              }`}
+              slotProps={{
+                htmlInput: {
+                  maxLength: VENDOR_NOTES_MAX_LENGTH,
+                  style: {
+                    overflowWrap: "anywhere",
+                    whiteSpace: "pre-wrap",
+                  },
+                },
+              }}
             />
           )}
         />
@@ -324,23 +348,22 @@ function TechnicianRow({
         tradeOptions={tradeOptions}
         tradeOptionsLoading={tradeOptionsLoading}
       />
-      {showStatus && (
-        <Controller
-          control={control}
-          name={`technicians.${index}.isActive`}
-          render={({ field }) => (
-            <FormControlLabel
-              control={
-                <Switch
-                  checked={field.value}
-                  onChange={(_event, checked) => field.onChange(checked)}
-                />
-              }
-              label={field.value ? "Active" : "Inactive"}
-            />
-          )}
-        />
-      )}
+      <Controller
+        control={control}
+        name={`technicians.${index}.isActive`}
+        render={({ field }) => (
+          <FormControlLabel
+            sx={{ display: showStatus ? undefined : "none" }}
+            control={
+              <Switch
+                checked={Boolean(field.value)}
+                onChange={(_event, checked) => field.onChange(checked)}
+              />
+            }
+            label={field.value ? "Active" : "Inactive"}
+          />
+        )}
+      />
     </Stack>
   );
 }
diff --git a/src/app/(protected)/vendors/_components/vendor-roster-page.tsx b/src/app/(protected)/vendors/_components/vendor-roster-page.tsx
index 45f1bb19..45a1c823 100644
--- a/src/app/(protected)/vendors/_components/vendor-roster-page.tsx
+++ b/src/app/(protected)/vendors/_components/vendor-roster-page.tsx
@@ -140,7 +140,7 @@ export default function VendorRosterPage({ vendorId, companyId }: VendorRosterPa
             >
               Cancel
             </Button>
-            <Button type="submit" variant="contained" disabled={form.isSaving || !form.isValid}>
+            <Button type="submit" variant="contained" disabled={form.isSaving}>
               {submitLabel(form.isSaving, isEdit)}
             </Button>
           </Stack>
diff --git a/src/domain/vendors/schemas/vendor-roster-schema.ts b/src/domain/vendors/schemas/vendor-roster-schema.ts
index 9358b12b..744a3581 100644
--- a/src/domain/vendors/schemas/vendor-roster-schema.ts
+++ b/src/domain/vendors/schemas/vendor-roster-schema.ts
@@ -35,6 +35,8 @@ const northAmericanPhone = z
 
 const optionalEmail = z.union([z.string().email("Invalid email"), z.literal("")]);
 
+export const VENDOR_NOTES_MAX_LENGTH = 500;
+
 export const rosterTechnicianSchema = z.object({
   id: z.union([z.string(), z.number()]).optional(),
   contactName: z.string(),
@@ -56,7 +58,9 @@ const baseCompanyFields = {
   state: z.string(),
   zip: z.string(),
   googleMapsUrl: httpsUrl,
-  notes: z.string(),
+  notes: z
+    .string()
+    .max(VENDOR_NOTES_MAX_LENGTH, `Notes must be ${VENDOR_NOTES_MAX_LENGTH} characters or fewer`),
   technicians: z.array(rosterTechnicianSchema),
 };
 
@@ -67,7 +71,7 @@ export const vendorCompanyRosterSchema = z.object(baseCompanyFields).superRefine
     ctx.addIssue({
       code: z.ZodIssueCode.custom,
       path: ["companyPhone"],
-      message: "Company phone or email is required",
+      message: "Provide a company phone or email (at least one required)",
     });
   }
 });
diff --git a/src/test/app/(protected)/vendors/use-vendor-roster-form.test.tsx b/src/test/app/(protected)/vendors/use-vendor-roster-form.test.tsx
index b56aa714..538aaf4b 100644
--- a/src/test/app/(protected)/vendors/use-vendor-roster-form.test.tsx
+++ b/src/test/app/(protected)/vendors/use-vendor-roster-form.test.tsx
@@ -1,7 +1,7 @@
 import { act, renderHook, waitFor } from "@testing-library/react";
 import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
 import type { ReactNode } from "react";
-import { useController } from "react-hook-form";
+import { useController, useFieldArray } from "react-hook-form";
 import { beforeEach, describe, expect, it, vi } from "vitest";
 
 const rosterGet = vi.fn();
@@ -321,6 +321,31 @@ describe("useVendorRosterForm prototype defaults", () => {
   });
 });
 
+describe("useVendorRosterForm technician removal", () => {
+  it("keeps a valid roster saveable after an existing technician is removed", async () => {
+    rosterQueryResult = {
+      data: rosterWithTechnicians,
+      isLoading: false,
+      isError: false,
+      error: null,
+      refetch: vi.fn(),
+    };
+    const { result } = renderHook(
+      () => {
+        const form = useVendorRosterForm({ mode: "update", companyId: 5 });
+        const technicians = useFieldArray({ control: form.control, name: "technicians" });
+        return { form, technicians };
+      },
+      { wrapper: makeWrapper(createClient()) },
+    );
+
+    await waitFor(() => expect(result.current.form.isValid).toBe(true));
+    act(() => result.current.technicians.remove(1));
+
+    await waitFor(() => expect(result.current.form.isValid).toBe(true));
+  });
+});
+
 describe("useVendorRosterForm stale-selection handling", () => {
   beforeEach(() => {
     rosterGet.mockReset();
diff --git a/src/test/app/(protected)/vendors/vendor-create-modal.test.tsx b/src/test/app/(protected)/vendors/vendor-create-modal.test.tsx
new file mode 100644
index 00000000..661f00d7
--- /dev/null
+++ b/src/test/app/(protected)/vendors/vendor-create-modal.test.tsx
@@ -0,0 +1,52 @@
+import { fireEvent, screen, waitFor } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import { describe, expect, it, vi } from "vitest";
+import { VendorCreateModal } from "@/app/(protected)/vendors/_components/vendor-create-modal";
+import { renderWithProviders } from "@/test/test-utils";
+
+vi.mock("@/domain/vendors/use-cases/use-vendor-facets", () => ({
+  useVendorFacets: () => ({ data: { companies: [], trades: [] }, isLoading: false }),
+}));
+
+vi.mock("@/domain/vendors/use-cases/use-save-vendor-company-roster", async () => {
+  const actual = await vi.importActual<
+    typeof import("@/domain/vendors/use-cases/use-save-vendor-company-roster")
+  >("@/domain/vendors/use-cases/use-save-vendor-company-roster");
+  return {
+    ...actual,
+    useSaveVendorCompanyRoster: () => ({ mutate: vi.fn(), isPending: false }),
+  };
+});
+
+describe("VendorCreateModal validation", () => {
+  it("explains the company phone-or-email requirement after submission", async () => {
+    renderWithProviders(<VendorCreateModal open={true} onClose={vi.fn()} />, {
+      route: "/vendors",
+      withAuth: false,
+    });
+
+    fireEvent.change(screen.getByRole("combobox", { name: /Company/ }), {
+      target: { value: "Gateway Plumbing" },
+    });
+    await userEvent.click(screen.getByRole("button", { name: "Add Vendor" }));
+
+    expect(
+      await screen.findByText("Provide a company phone or email (at least one required)"),
+    ).toBeInTheDocument();
+  });
+
+  it("shows the notes limit and live character counter", async () => {
+    renderWithProviders(<VendorCreateModal open={true} onClose={vi.fn()} />, {
+      route: "/vendors",
+      withAuth: false,
+    });
+
+    const notes = screen.getByRole("textbox", { name: "Notes (optional)" });
+    fireEvent.change(notes, { target: { value: "abc" } });
+
+    expect(notes).toHaveAttribute("maxlength", "500");
+    await waitFor(() =>
+      expect(notes).toHaveAccessibleDescription(/3\/500 characters · Maximum 500 characters/),
+    );
+  });
+});
diff --git a/src/test/app/(protected)/vendors/vendor-detail-drawer.test.tsx b/src/test/app/(protected)/vendors/vendor-detail-drawer.test.tsx
index 4e52aa7f..a882b91f 100644
--- a/src/test/app/(protected)/vendors/vendor-detail-drawer.test.tsx
+++ b/src/test/app/(protected)/vendors/vendor-detail-drawer.test.tsx
@@ -1,16 +1,27 @@
-import { screen } from "@testing-library/react";
+import { screen, waitFor } from "@testing-library/react";
 import userEvent from "@testing-library/user-event";
-import { describe, expect, it, vi } from "vitest";
+import { beforeEach, describe, expect, it, vi } from "vitest";
 import { VendorDetailDrawer } from "@/app/(protected)/vendors/_components/vendor-detail-drawer";
 import { renderWithProviders } from "@/test/test-utils";
 import type { VendorListItem } from "@/domain/vendors/types/vendor";
 
 const useVendorCompanyRoster = vi.fn();
+const saveMutate = vi.fn();
 
 vi.mock("@/domain/vendors/use-cases/use-vendor-company-roster", () => ({
   useVendorCompanyRoster: (...args: unknown[]) => useVendorCompanyRoster(...args),
 }));
 
+vi.mock("@/domain/vendors/use-cases/use-save-vendor-company-roster", async () => {
+  const actual = await vi.importActual<
+    typeof import("@/domain/vendors/use-cases/use-save-vendor-company-roster")
+  >("@/domain/vendors/use-cases/use-save-vendor-company-roster");
+  return {
+    ...actual,
+    useSaveVendorCompanyRoster: () => ({ mutate: saveMutate, isPending: false }),
+  };
+});
+
 const vendor: VendorListItem = {
   id: 1,
   companyId: "co-1",
@@ -50,7 +61,111 @@ function rosterWith(technicians: Array<Record<string, unknown>>) {
   };
 }
 
+beforeEach(() => {
+  saveMutate.mockReset();
+});
+
 describe("VendorDetailDrawer selected-technician display", () => {
+  it.each([
+    { removedPosition: 1, remainingId: 2, remainingName: "Beth" },
+    { removedPosition: 2, remainingId: 1, remainingName: "Adam" },
+  ])(
+    "reconciles the remaining roster after removing technician $removedPosition",
+    async ({ removedPosition, remainingId, remainingName }) => {
+      useVendorCompanyRoster.mockReturnValue(
+        rosterWith([
+          {
+            id: 1,
+            contactName: "Adam",
+            phone: "314-555-0198",
+            email: "",
+            tradeSpecialties: "",
+            isActive: removedPosition === 1,
+            totalJobs: 5,
+          },
+          {
+            id: 2,
+            contactName: "Beth",
+            phone: "314-555-0199",
+            email: "",
+            tradeSpecialties: "",
+            isActive: removedPosition === 2,
+            totalJobs: 2,
+          },
+        ]),
+      );
+
+      renderWithProviders(
+        <VendorDetailDrawer open={true} vendor={vendor} startInEdit={true} onClose={vi.fn()} />,
+        { route: "/vendors", withAuth: false },
+      );
+
+      await userEvent.click(
+        screen.getByRole("button", { name: `Remove technician ${removedPosition}` }),
+      );
+      await userEvent.click(screen.getByRole("button", { name: "Save changes" }));
+
+      await waitFor(() => expect(saveMutate).toHaveBeenCalledTimes(1));
+      expect(saveMutate).toHaveBeenCalledWith(
+        expect.objectContaining({
+          mode: "update",
+          values: expect.objectContaining({
+            technicians: [
+              expect.objectContaining({
+                id: remainingId,
+                contactName: remainingName,
+                isActive: false,
+              }),
+            ],
+          }),
+        }),
+        expect.any(Object),
+      );
+    },
+  );
+
+  it("keeps Save changes available after removing a technician from a legacy roster", async () => {
+    const roster = rosterWith([
+      {
+        id: 1,
+        contactName: "Adam",
+        phone: "314-555-0198",
+        email: "",
+        tradeSpecialties: "",
+        isActive: true,
+        totalJobs: 5,
+      },
+      {
+        id: 2,
+        contactName: "Beth",
+        phone: "314-555-0199",
+        email: "",
+        tradeSpecialties: "",
+        isActive: true,
+        totalJobs: 2,
+      },
+    ]);
+    roster.data.companyPhone = "";
+    roster.data.email = "";
+    useVendorCompanyRoster.mockReturnValue(roster);
+
+    renderWithProviders(
+      <VendorDetailDrawer open={true} vendor={vendor} startInEdit={true} onClose={vi.fn()} />,
+      { route: "/vendors", withAuth: false },
+    );
+
+    await userEvent.click(screen.getByRole("button", { name: "Remove technician 2" }));
+
+    const save = screen.getByRole("button", { name: "Save changes" });
+    expect(save).toBeEnabled();
+
+    await userEvent.click(save);
+
+    expect(
+      await screen.findByText("Provide a company phone or email (at least one required)"),
+    ).toBeInTheDocument();
+  });
+
   it("renders no preference label when preferredContact is absent", () => {
     useVendorCompanyRoster.mockReturnValue(
       rosterWith([
@@ -137,6 +252,38 @@ describe("VendorDetailDrawer selected-technician display", () => {
 });
 
 describe("VendorDetailDrawer design parity", () => {
+  it("wraps long unbroken company notes inside the drawer", () => {
+    const roster = rosterWith([]);
+    roster.data.notes = "x".repeat(5000);
+    useVendorCompanyRoster.mockReturnValue(roster);
+
+    renderWithProviders(<VendorDetailDrawer open={true} vendor={vendor} onClose={vi.fn()} />, {
+      route: "/vendors",
+      withAuth: false,
+    });
+
+    const notes = screen.getByText("x".repeat(5000));
+    expect(notes).toHaveStyle({ overflowWrap: "anywhere", whiteSpace: "pre-wrap" });
+  });
+
+  it("preserves an oversized legacy note in edit mode while showing the new limit", async () => {
+    const roster = rosterWith([]);
+    const legacyNotes = "x".repeat(501);
+    roster.data.notes = legacyNotes;
+    useVendorCompanyRoster.mockReturnValue(roster);
+
+    renderWithProviders(
+      <VendorDetailDrawer open={true} vendor={vendor} startInEdit={true} onClose={vi.fn()} />,
+      { route: "/vendors", withAuth: false },
+    );
+
+    const notes = await screen.findByRole("textbox", { name: "Notes (optional)" });
+    expect(notes).toHaveValue(legacyNotes);
+    expect(notes).toHaveAttribute("maxlength", "500");
+    expect(notes).toHaveStyle({ overflowWrap: "anywhere", whiteSpace: "pre-wrap" });
+    expect(screen.getByText(/501\/500 characters/)).toBeInTheDocument();
+  });
+
   it("renders the company once when there is no technician name to head the panel", () => {
     useVendorCompanyRoster.mockReturnValue(rosterWith([]));
 
diff --git a/src/test/domain/vendors/schemas/vendor-roster-schema.test.ts b/src/test/domain/vendors/schemas/vendor-roster-schema.test.ts
index 6b94dd90..646f8e73 100644
--- a/src/test/domain/vendors/schemas/vendor-roster-schema.test.ts
+++ b/src/test/domain/vendors/schemas/vendor-roster-schema.test.ts
@@ -3,6 +3,7 @@ import {
   emptyRosterTechnician,
   emptyVendorCompanyRosterForm,
   isAbsoluteHttpsUrl,
+  VENDOR_NOTES_MAX_LENGTH,
   vendorCompanyRosterSchema,
   vendorCompanyRosterUpdateSchema,
 } from "@/domain/vendors/schemas/vendor-roster-schema";
@@ -28,7 +29,9 @@ describe("vendorCompanyRosterSchema", () => {
     expect(result.success).toBe(false);
     if (!result.success) {
       expect(
-        result.error.issues.some((issue) => issue.message === "Company phone or email is required"),
+        result.error.issues.some(
+          (issue) => issue.message === "Provide a company phone or email (at least one required)",
+        ),
       ).toBe(true);
     }
   });
@@ -54,6 +57,20 @@ describe("vendorCompanyRosterSchema", () => {
     expect(result.success).toBe(true);
   });
 
+  it("accepts exactly 500 note characters and rejects 501", () => {
+    const atLimit = vendorCompanyRosterSchema.safeParse({
+      ...baseCompany,
+      notes: "x".repeat(VENDOR_NOTES_MAX_LENGTH),
+    });
+    const overLimit = vendorCompanyRosterSchema.safeParse({
+      ...baseCompany,
+      notes: "x".repeat(VENDOR_NOTES_MAX_LENGTH + 1),
+    });
+
+    expect(atLimit.success).toBe(true);
+    expect(overLimit.success).toBe(false);
+  });
+
   it("accepts a technician row without a name or phone", () => {
     const result = vendorCompanyRosterSchema.safeParse({
       ...baseCompany,