Contract Payment & Milestone Billing

We build a proper Frappe app that closes this gap. A new Contract Billing Plan DocType links to the standard Contract and holds a child table of milestones (description, planned value or percentage, planned date, status, retention percentage). A whitelisted server method generates a draft Sales Invoice from a milestone in one click, stamping the contract and milestone references onto the invoice, applying the retention deduction as a line against a configurable retention-receivable account, and writing the certified value back to the plan. hooks.py doc_events on Sales Invoice and Payment Entry (on_submit, on_cancel) keep certified, invoiced, paid, and retention-held figures in sync on the contract, so cancelling an invoice cleanly reverses the milestone status instead of leaving stale totals. A separate retention-release workflow (a Retention Release DocType with a Frappe Workflow: Draft to Reviewed to Approved) generates the final retention invoice or credit only when the release condition is approved, with role-gated approval.

On top of the data model we build the reports and controls finance actually asks for: an "Outstanding by Contract" query report (contract value, certified, invoiced, paid, retention held, balance to bill, overdue), a client script on the Sales Invoice that surfaces the linked contract and remaining billable balance inline, permission rules and a "Contract Billing" role profile so project managers can raise milestone invoices but only finance approves retention release, and a scheduler event that flags milestones whose planned date has passed without certification. Everything is exposed over the Frappe REST API and whitelisted methods so your project system or a client portal can read contract billing status programmatically. The app targets ERPNext v15 and is tested for the v16 line.

Because this is build-to-order, nothing is a black-box download. After a short scoping call we confirm your milestone and retention rules, chart-of-accounts mapping, and approval roles in a written scope, then build against your requirements. You get the installable app source for your version, install and configuration on your bench, UAT on a staging site with a rollback plan, and a post-go-live support window. Typical delivery is 2-4 weeks from confirmed scope.