Build each project’s billing schedule of values from its QBO cost-code breakdown. Combine codes into client-facing lines or add custom ones — the total must equal the contract. The Billing portal bills (AIA G702/G703) off this schedule.
Income accounts
These map to your QuickBooks Online income accounts (parent: Sales). Mostly fixed — edit here if your chart of accounts changes. Account # can be left blank (e.g. "Other").