Legal Question in Credit and Debt Law in California

It really depends on what the contract says and the terms of the estimate. If the contract says that you pay per pound and the mover's initial estimate of the weight is incorrect, you still might be on the hook. On the other hand, the mover might have provide you a contract that provides for a flat fee and then the move might have taken the risk if the estimate should have been higher.

Read the contract carefully or take it to a local attorney for further advice.