Once you have mutual acceptance you have a legal contract. The seller has made his/her decision to enter into the agreement with you based on what items were or were not included in the offer.
Any contingencies asked for after mutual acceptance would have no bearing on the contract already in place. The seller, out of the goodness of his/her heart, might choose to consider and sign a contingency, but is under absolutely no obligation to do so.
Please feel free to contact me with any further questions.
Certified Buyer Representative
Century 21 Princeton Properties