Start with the reason this software development agency should exist, not a list of screens. Which people will use it day to day, with what frequency, and what happens today? A vendor who understands the goal will suggest a simpler way to reach it; a team that receives only a feature list prices the list as written.
Set out the scope as concrete flows: a walk through each important path. Every bit as useful, list what is out of scope. An explicit exclusion list saves more argument at delivery time than almost anything else in the document. Indicate as well which items are decided fintech and crypto software development company which are still open — the difference between nearshore and offshore development changes the price, and pretending everything is fixed only hurts you.
List the constraints. These include systems you must integrate with, the data you already hold and its condition, security and compliance rules, traffic expectations, supported browsers or devices and infrastructure that is already decided. Where a date is genuinely fixed, say why hire a dedicated team instead of freelancers: a team is usually able to rearrange the plan to protect it, but only if they know it exists.
Write down what completion means feature by feature. Clear acceptance criteria do not need special syntax: a plain-language note describing what must be true when the feature works is sufficient. That one addition reduces the review at the end by a surprising margin and removes the usual argument at handover.
To close, state what you want in the response. Ask for a breakdown by feature or module, the assumptions behind each number, the main risks and an optimistic and a pessimistic figure. Take a broad range as useful information rather than evasion: it tells you where your description is thin. From there rewrite that part and request a revised number — the second estimate is far closer to reality.