Start with the business problem, not a list of screens. Which people will use it day to day, with what frequency, and what happens today? An estimator who knows what you are trying to achieve often proposes an alternative that costs less; a team that receives only the requirements as given will price the list as written.

Define what is included as concrete flows: a walk through each important path. Just as important, list what the first release deliberately excludes. An explicit list of exclusions prevents more disagreement later than almost anything else in the document. Also mark which items are decided and vue js vs angular which are still open — the difference changes the price, and concealing the open questions helps nobody.

Write down the hard constraints. The list covers existing systems the software has to talk to, existing databases and their quality, regulatory obligations, traffic expectations, which devices matter time and materials vs fixed price contract infrastructure that is already decided. If a deadline is real, say why: a good team is usually able to rearrange the plan to protect it, but not if the date is a secret.

Say what completion means for each item. Testable acceptance criteria do not need any formal notation: a plain-language note describing the expected behaviour will do. That one addition compresses the review at the end considerably and eliminates most late-stage disagreement.

Finally, state what you want in the response. Ask for an itemised estimate, the assumptions used, the main risks and an optimistic and a pessimistic figure. Read a wide range as useful information rather than evasion: it usually points to where your description is thin. Then clarify that area and ask for a new estimate — the revised figure is the one worth planning around.