The short answer
Demand, usable context, rights, coverage and deal terms can all influence a proposal. There is no dependable conversion from employee count to payout.
Ask for the assumptions
Which systems and years does the number cover? Which rights are included? What quality or acceptance checks can reduce it?
Separate preparation from price
Identify work and third-party costs that you bear. Compare guaranteed net proceeds and optional upside rather than combining them into a single optimistic number.
What to record before deciding
Keep the written scope, official provider source, unresolved questions and the person responsible for each check. Treat a marketing claim as a claim until it is reflected in the agreement. A directory entry does not approve the transaction or establish your rights to share the records.