Also include client promises into the contract, e.g.
bank has enough people for UATs,
all the internal law is set and known and not be constructed during project,
agree or declare that only one criterium is the most important one in the project (well known PM trianggle).
If they don't want to meet you and discuss more deeply some of reqs you need to prepare a RFP - suspect cheating and estimate very carefully.
For sure the list is longer than this few points...
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