I have an opportunity to buy a 1965 Mustang Fastback that needs a full restoration. What would you offer for this?

The car obviously has some pretty bad rust, and is in need of some major body work. I have not yet seen the car in person, and before wasting the owners time, I just wanted to get an opinion on whether this car is even worth fooling with. The cowl, front shock towers, firewall, and probably a lot of other sheet metal needs to be replaced. The photos attached were provided by the current owner who replaced the floor pans, left rear quarter, left rocker panel, left rear wheel well, rear panel, and trunk pan. He has the rear glass as well as some additional sheet metal that he will include with the sale. I'm not sure of the quality or craftsmanship of the current owner's work up until this point. The sale will not include the motor or tranny. I am not sure how the car originally came from the factory or its VIN#, but it appears this was an original V8 car as the axles have 5 lugs (assuming the axles are original). This would be my first vehicle restoration, but this is one of my dream cars. How much would those of you with experience pay for this Fastback in its current condition? Any advice is appreciated.

Pics