Hemma's standard budget structure for a Belgian build. Fourteen top-level categories — site work, foundations, structure, roofing, the lot — broken down into the items most projects need.
Every new project starts with this template instantiated as its budget tree. You don't have to keep all of it: prune the lines you don't need, add lines for anything bespoke, and the rollups still work.
The template is also what the budget mapping wizard aligns imported Excel budgets against, which is how invoices end up linked to the right line.