The professional fees look comparable but the scope isn't
Similar-looking proposals can cover different stages, duties and extras, so the cheaper fee may not buy the same work.
What's happening?
An architect, engineer or other consultant can price by percentage, lump sum or time, and each proposal may stop at a different stage. Drawings, coordination, tender support and site duties can be included, excluded or treated as additional work, even where two headline fees look close.
A useful comparison starts with the work the project needs, then maps each proposal against it. That exposes duties with no owner and shows which questions need answers before an appointment is signed; it does not decide who to appoint or provide legal advice on the terms.
The solution
Set the proposals against the same required scope before comparing their fees.
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