One price book
Rates live in one place and every quote reads from them, so a wall is one price everywhere. An override is allowed, and it is flagged.
Every quote reads from the same price book, is itemised by stage, and turns into a payment schedule that can never disagree with it. Then invoice and get paid, in stages, with the numbers already right.

Partly available The core of this is in the product today. The lists below say what works and what is still to come.
Rates live in one place and every quote reads from them, so a wall is one price everywhere. An override is allowed, and it is flagged.
Customers get the stages priced separately instead of one lump sum, and you can back-cost a rate from a target price.
Deposit, stage payments and retention are generated from the quote and must total 100%. Variations are separate lines with a reason.
Everything in this list is in the product now.
Bring in a takeoff from an Excel export instead of retyping it, and price it from your price book.
Customers accept online. Acceptance issues the agreement, insurances and the payment schedule.
Stage claims go out as invoices, card payments and Tap to Pay are taken on any phone, and it all syncs to your accounting.

Compare what each plan includes on the pricing page.