Start with the reason this software should exist, not a list of screens. What kind of user will use the system, with what frequency, and what happens today? An estimator who understands the goal can propose a cheaper route to it; one who only sees the requirements as given can only price the list as written.

Describe the scope as concrete flows: what the user does and what the system does in response. Just as important, list what is out of scope. An explicit list of exclusions saves more friction later than any other single page. Also mark which items are decided and which are still open — honest teams price those differently, difference between livewire and react concealing the open questions helps no one.

Write down the hard constraints. These include systems you must integrate with, the data you already hold and its condition, compliance requirements, traffic expectations, supported browsers or devices and stacks you cannot change. Where a date is genuinely fixed, say why: a good team will often resequence the work to meet it, provided they hear about it early.

Define what the word done means feature by feature. Testable acceptance criteria need not use special syntax: a short list describing what must be true when the feature works is enough. This single habit compresses acceptance testing dramatically and closes off the usual argument at handover.

To close, state what you want in the response. Ask for an itemised estimate, the assumptions used, the risks the team sees and a low number and a high number. Take a broad range as information, not evasion: it normally identifies where your description is thin. Then tighten that section and request hire a full stack developer revised number — the revised figure tends to be far closer to reality.