Open with the problem you are solving, not a feature list. Which people will use it day to day, custom software development pricing in uk how often, and what happens today? A vendor who grasps the purpose often proposes an alternative that costs less; one who only sees a list of screens prices your assumptions along with the work.
Define what is included as short scenarios: aws consulting services what the user does and what the system does in response. Every bit as useful, state explicitly what the first release deliberately excludes. A written out-of-scope list removes more disagreement later than almost anything else in the document. Also mark which items are decided and which are still under discussion — the difference changes the price, and concealing the open questions helps no one.
Write down the hard constraints. This means the platforms and rust consulting services involved, the data you already hold and its condition, regulatory obligations, user volumes, which devices matter and stacks you cannot change. Where a date is genuinely fixed, say why: an experienced team can often resequence the work to hit it, but only if they know it exists.
Define what done means for the important items. Testable acceptance criteria need not use special syntax: a short list stating what a user should be able to do is enough. This single habit reduces acceptance testing dramatically and eliminates the most common source of disputes.
One last thing, state what you want in the response. Ask for an itemised estimate, the assumptions behind each number, the risks the team sees and an optimistic and a pessimistic figure. Take a broad range as information, not evasion: it tells you exactly which requirement is unclear. From there clarify that area and ask for a new estimate — the next version will be the one worth planning around.