Legal Question in Real Estate Law in California

Your written contract that was agreed upon determines the purchase price. You have that in front of you, and it should tell you who is responsible for what repairs, and what items are considered contingencies. You may want to consult in person with an attorney and have them review the contract.

The terms in the signed contract will govern if this progresses to litigation, but it might be quicker, cheaper and easier to relent and accept the proposed change without escalating the battle. The boundary between what's legally enforceable and what's a common-sense concession is often very fuzzy. Maybe this seller just needs to be told he's being a jerk.

Assuming you mean you are the buyer and have a valid written contract with all the terms properly included, then the seller can't change those terms in escrow without all parties agreement. You wouldn't have to agree. But, see Mr Whipple's reasonable advice.