I am thinking of buying a 1988 Rx-7 Turbo w/ 154,000, I was just wondering if I was to buy it and rebuild the engine, how much would it cost to rebuild the engine on average, how reliable will the engine be after the rebuild, and also are the parts super expensive as some people say?
remember that this is an old car and you'll have some of the same issues that most cars do at that age and mileage. "reliability" is a somewhat relative thing. If you're not prepared for the little bullshit that comes with any car that has 18 years on it then buy something with a warranty.
If you have a fresh rebuild in there and tune it properly you shouldn't have many rotary-specific problems. All this **** you hear about blown motors is because either the motor was high mileage, improper tuning, or in some cases freak accidents that often happen to heavily modified cars.
You still need to do reliability stuff like cleaning the injectors, replacing clogged cats, etc
Replace all the hoses and vac lines when its out getting a rebuild. Once you do that, you should be good to go. There will prob be a few little problems, but nothing major. The only problem I've ever had with mine was a blown engine, and that happened after 215k miles and lots of track time.