Separate labor from uncertainty
Effort estimates are only part of fixed-bid pricing. Unclear scope, slow feedback, weak access, and ambiguous acceptance criteria all increase delivery risk.
If the brief hides important details, either ask before pricing or bound the first milestone tightly.
Write the risk into the proposal
A pricing note helps the client understand what is included and where scope could change. This is especially useful when prep cost or unknown implementation cost is material.
Good pricing copy reduces surprise later. It also filters clients who expected unlimited work inside a fixed bid.