Fix the scope before seeking the quotes
The single most useful thing a committee can do happens before any bidder is contacted. Write down the areas to be cleaned, the tasks in each and the frequency you expect, and send that same document to everyone. It does not need to be elaborate; a two-page list covering entry, lobby, lifts, corridors, stairs, bin room, car park and any shared amenity is enough to make the responses comparable.
Without a common document, each provider proposes their own version of the work. One includes the car park, another does not. One collects and presents bins, another leaves them. The totals then differ for reasons nobody at the meeting can identify, and the discussion turns into an argument about price when the real difference is scope. Writing the document once also means it can be reused at the next tender without starting again.
