85 RX7 Driveability Question
 

I hope I'm welcome here... not a current RX7 owner, but looking at one. The seller describes the following: car started to run rough, looked under the hood, found plug wire disconnected; re-connected wire, ran OK for awhile, then started acting as if it was running out of gas. Seller has only owned for a month; doesn't know anything about the rotary and decided to sell rather than fix. Mechanic he took it to doesn't know rotaries either. Is this a "typical" symptom? I'm intrigued, as the car is otherwise in good shape although it has 200,000 miles on it. How durable are these cars? Should I avoid such high mileage? Thanks!