Milestone billings (BAST), project deposits, and warranty retention
Interior billings follow phases: upfront deposits, site milestone progress under BAST sign-offs, and 5% retention after warranty periods. Under VAT Law Article 13(1a) and PER-11/PJ/2025 Article 31(2), Tax Invoices must be issued when deposits clear or when BAST milestone certificates are executed. Neracia maps project timelines so draft invoices are ready for approval before the 20th.