I have a 1985 Nisson 300ZX. I am the only owner. 9000 miles and has never seen snow. Kept in a storage building for the last 10 yrs. Carpet and padding underneath it. Car cover on it. Black w/gold pin

I would fix it and drive it. You will have considerable expenses though. The fuel system will need cleaning out, the brake system should be redone and I would replace all the cooling system hoses and belts.

Replace the tires too.

Have it inspected and serviced by a mechanic, maybe spring for a CPO (certified pre owned), then get the car detailed, get the best photos you can, maybe spring for a pro that specializes in cars. You have a super low mileage one owner 300ZX, so if you want to get the max out of it from a sale, gotta present the car in the best possible light.

A web site like Bring a Trailer would be a good place to sell it on commission, and they tend to cater to the collector crowd and cars there seem to fetch amazing prices. They screen the cars they will allow, from your description yours would be a good candidate.