Start with the business problem, lms development company not a list of screens. What kind of user will use it day to day, how often, and what happens today? An estimator who knows what you are trying to achieve often proposes a simpler way to reach it; one who only sees a list of screens prices the list as written.
Set out the scope as short scenarios: what the user does and what the system does in response. Just as important, write down what the first release deliberately excludes. An explicit list of exclusions prevents more argument during acceptance than almost anything else in the document. Mark too which decisions are settled and which are still open — the difference changes the price, and difference between vue and react hiding it helps nobody.
Write down the hard constraints. These include the platforms and services involved, existing databases and their quality, regulatory obligations, traffic expectations, target platforms and any technology you are committed to. Where a date is genuinely fixed, explain what drives it: a team will often cut the right scope to meet it, provided they hear about it early.
Define what done means for each item. Clear acceptance criteria do not need any formal notation: a short paragraph describing the expected behaviour is sufficient. This single habit shortens the review at the end by a surprising margin and removes the usual argument at handover.
Finally, ask for a specific format. Request a breakdown by feature or module, the assumptions used, the main risks and a low number and a high number. Read a wide range as information, not evasion: it tells you where your description is thin. From there clarify that area and ask for a new estimate — the next version is the one worth planning around.