Rent Schedule Engine

The rent schedule engine lets agents generate, preview, and manage rent payment schedules for tenancy terms. Schedules can be auto-calculated from term parameters or built manually entry by entry.

Overview

Each tenancy term can have a set of rent_schedule_payments — individual payment entries that together form the complete schedule. Each entry records:

• Amount (in pence, integer)
• Due date
• Period start / end
• Label (e.g. "Month 1", "Pro-rata (partial week)")
• Type flags: isProRata, isCustom
• Sort order for display
• Notes for agent annotations

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UI Panel

The <RentSchedulePanel> component is embedded on the tenancy term detail page. It exposes three tabs:

Schedule Tab

Displays all saved payment entries in a table with:

Column	Description
#	Sort order
Label	Entry name and optional note
Due Date	Formatted payment due date
Amount	Payment amount (£)
Running Total	Cumulative total at this row
Type	Standard, Pro-rata, or Custom badge
Actions	Remove individual entry

A summary bar at the top shows the overall total and payment count. A Clear All button removes the entire schedule after confirmation.

If payments do not sum correctly against the expected total, a discrepancy indicator is shown.

Generate Tab

Auto-computes a schedule from the tenancy term's parameters.

Configurable options:

• Frequency: Monthly, Weekly, or Custom
• Due day: Day of the month/week the payment falls on
• Start date / End date: Override or inherit from the tenancy term

Preview before saving: The panel calls the preview procedure first so the agent can review the calculated entries before they are committed to the database. Generating a schedule replaces any existing one.

Custom Tab

Manually define individual payment entries.

• Add entries with amount, due date, label, and optional notes.
• Choose Replace mode to overwrite the existing schedule, or Append mode to add entries to it.

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Calculation Logic

The generateRentSchedule() utility produces entries based on frequency:

Monthly

1. Pro-rata first period — from the start date to the end of the first calendar month (if the start date is not the 1st).
2. Full monthly entries — one entry per full calendar month.
3. Pro-rata last period — from the start of the final partial month to the end date (if the end date is not the last day of the month).

Weekly

• Weekly rent is derived from the monthly figure: monthlyRent × 12 ÷ 52.
• Partial weeks at the start and end of the term are pro-rated.

Custom

• Returns an empty schedule. The agent is expected to populate entries manually using the Custom tab.

All amounts are stored and calculated as pence (integers) to avoid floating-point rounding errors.

Validation

validateScheduleTotal() sums all entry amounts and compares the result to the expected total. A discrepancy of up to £1 is tolerated to account for rounding across pro-rata periods.

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tRPC API Reference

All procedures live under the rentSchedule router.

rentSchedule.preview

Stateless calculation — returns computed entries without persisting.

const result = await trpc.rentSchedule.preview.query({
  tenancyTermId: string,
  frequency: "monthly" | "weekly" | "custom",
  startDate: string,   // ISO date
  endDate: string,     // ISO date
  monthlyRentPence: number,
  dueDay?: number,
});

rentSchedule.generate

Computes and persists a schedule, replacing any existing entries.

await trpc.rentSchedule.generate.mutate({
  tenancyTermId: string,
  frequency: "monthly" | "weekly" | "custom",
  startDate: string,
  endDate: string,
  monthlyRentPence: number,
  dueDay?: number,
});

rentSchedule.list

Fetches saved entries sorted by sortOrder, along with a running total and entry count.

const { entries, totalPence, entryCount } =
  await trpc.rentSchedule.list.query({ tenancyTermId: string });

rentSchedule.saveCustomEntries

Saves manually defined entries. Supports replace (overwrites) or append (adds to existing).

await trpc.rentSchedule.saveCustomEntries.mutate({
  tenancyTermId: string,
  mode: "replace" | "append",
  entries: Array<{
    label: string,
    amountPence: number,
    dueDate: string,
    periodStart?: string,
    periodEnd?: string,
    notes?: string,
  }>,
});

rentSchedule.deleteEntry

Removes a single payment entry by ID.

await trpc.rentSchedule.deleteEntry.mutate({ id: string });

rentSchedule.clearSchedule

Bulk-deletes all entries for a given tenancy term.

await trpc.rentSchedule.clearSchedule.mutate({ tenancyTermId: string });

rentSchedule.validate

Checks whether saved entries sum to the expected total (£1 tolerance).

const { isValid, discrepancyPence } =
  await trpc.rentSchedule.validate.query({
    tenancyTermId: string,
    expectedTotalPence: number,
  });

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Audit Logging

All mutating procedures (generate, saveCustomEntries, deleteEntry, clearSchedule) emit audit log entries so changes to a rent schedule are fully traceable.