Start with the problem you are solving, not a feature list. What kind of user will use this, how often, and how is the job done today? A vendor who grasps the purpose often proposes an alternative that costs less; one who only sees the requirements as given prices your assumptions along with the work.
Define what is included as user stories or scenarios: who does what, and what happens next. Just as important, write down what you are not building. An explicit exclusion list removes more argument at delivery time than almost anything else in the document. Indicate as well which decisions are settled and which are still under discussion — honest teams price those differently, and concealing the open questions only hurts you.
List the constraints. This means existing systems the software has to talk to, existing databases and enterprise .net development their quality, compliance requirements, expected load, target platforms and outsource kotlin development infrastructure that is already decided. Where a date is genuinely fixed, say what depends on it: a good team is usually able to resequence the work to protect it, but only if they know it exists.
Say what done means for each item. Clear acceptance criteria need not use special syntax: a plain-language note describing what a user should be able to do is sufficient. This one section shortens the review at the end considerably and removes the usual argument at handover.
One last thing, state what you want in the response. Request a breakdown by feature or module, the assumptions behind each number, the main risks and a range rather than a single figure. Treat a wide range as a signal about the brief: it usually points to where your description is thin. From there rewrite that part difference between laravel and wordpress ask again — the revised figure is much more reliable.