For foundation work bids, insist on one combined price
I have saved a lot of money and headaches on a variety of new houses with this very simple technique: When I get bids for the foundation work, I insist on one combined price, including both the excavation and the concrete. This way each concrete subcontractor gets a price from his favorite excavator, and submits one complete price. What this means to the general contractor is that you won’t find yourself faced with additional charges by the form setters for extra handwork on a hole that wasn’t to their liking. In my experience, this includes most holes ever dug.
Besides eliminating surprise extras after the competitive relationship is lost, this strategy also results in one less subcontract you will have to let, schedule, supervise and shuffle paper for. Perhaps the greatest advantage, however, lies in simply avoiding a conflict between two subcontractors, with you in the middle.
Douglass Ferrell, Trout Creek, MT