Begin with the problem you are solving, not your preferred technology. What kind of user will use the system, with what frequency, and what does the process look like without it? An experienced team who understands the goal often proposes a cheaper route to it; someone handed only the requirements as given can only price exactly what you asked for.
Describe the scope as short scenarios: a walk through each important path. Equally important, list what is out of scope. An explicit exclusion list removes more disagreement at delivery time than any other single page. Indicate as well laravel vs node js which is better parts are firm and which are still open — honest teams price those differently, and pretending everything is fixed helps no one.
List the constraints. The list covers systems you must integrate with, existing databases and their quality, security and compliance rules, expected load, supported browsers or devices and any technology you are committed to. If a deadline is real, say what depends on it: an experienced team will often cut the right scope to protect it, but only if they know it exists.
Write down what the word done means for each item. Clear acceptance criteria do not need formal language: a short paragraph stating the expected behaviour will do. This one section reduces the sign-off process by a surprising margin and closes off the most common source of disputes.
To close, state what you want in the response. Request a breakdown by feature monolith or microservices module, the assumptions used, the risks the team sees and a range rather than a single figure. Take a broad range as information, not evasion: it tells you where your description is thin. Then rewrite that part and ask again — the revised figure will be much more reliable.