Let's start by saying that we are not lawyers, and the only person that is licensed to give a professional advice is a licensed real estate attorney.
In my opinion, it depends on your contract and several other factors. If you used the standard Arizona contract you agreed to due diligence. In any case your agent should not be liable. As for the appraisser and other inspectors involved, it will depend.
See section 6b of the contract:
Square Footage: BUYER IS AWARE THAT ANY REFERENCE TO THE SQUARE FOOTAGE OF THE PREMISES, BOTH THE REAL PROPERTY (LAND) AND IMPROVEMENTS THEREON, IS APPROXIMATE. IF SQUARE FOOTAGE IS A MATERIAL MATTER TO THE BUYER, IT MUST BE INVESTIGATED DURING THE INSPECTION PERIOD."
Furhtermore section 6h of the contract specifies:
BUYERACKNOWLEDGMENT: BUYER RECOGNIZES, ACKNOWLEDGES, AND AGREES THAT BROKER(S) ARE NOT QUALIFIED, NOR LICENSED, TO CONDUCT DUE DILIGENCE WITH RESPECT TO THE PREMISES OR THE SURROUNDING AREA. BUYER IS INSTRUCTED TO CONSULT WITH QUALIFIED LICENSED PROFESSIONALS TO ASSIST IN BUYER'S DUE DILIGENCE EFFORTS.. BECAUSE CONDUCTING DUE DILIGENCE WITH RESPECT TO THE PREMISES AND THE SURROUNDING AREA IS BEYOND THE SCOPE OF THE BROKER'S EXPERTISE AND LICENSING, BUYER EXPRESSLY RELEASES AND HOLDS HARMLESS BROKER(S) FROM LIABILITY FOR ANYDEFECTS OR CONDITIONS THAT COULD HAVE BEEN DISCOVERED BY INSPECTION OR INVESTIGATION.
This makes sense since the only way to know the correct square footage is by measuring it, and if the buyer wants to be sure he will have to hire someone to measure it. Measuring the square footage is outside the duties of a selling agent.
But there are other factors to consider. Was the 2,683sf figure listed on the assesor's page? Did anybody certified that the property measured 2,683? Did the appraisal indicated that figure?
To be sure your best recourse will be to get the advice of an attorney.
ABR - Accredited Buyer Representative