What is the most you would pay for a 2004 mazda rx8?

For me, it would be based on the condition of the rotary engine. Its a fairly simple design, I would have it cracked open and looked into. Based on what the one Mazda mechanic tells me is what I would feel comfortable to pay for a 6 year old rotary engine. My concern would be the seal and the vacuum pressure in the engine unit. I would need to know those two things are in good shape. I can't put a price on what I would pay until I know about the shape of the rotary. The pro of any rotary is the harder you run it the better. Ideally, if you had to drive 1-2 hours back and forth to work everyday, the rotary is a gem. It is not suited for stop and start, it can, but it is not at its best. It has better gas mileage being in constant motion, though gas mileage is not its strong suit either. A rotary engine is far more capable of providing a longer service life than any piston engine because of fewer moving parts, but this comes at a price. Don't get me wrong the rotary is a marvelous engine, however, by today's standards its high maintenance. A rotary needs oil changed or added every 3000 miles, last I heard synthetic is not an option, synthetic is to slippery fouling things up, which makes it temperamental. Cold weather is hard to deal with because the engine is not warmed with a radiator, like a piston engine, its a different heat generating animal. It requires an uncommon discipline to turn it off and not start it immediately or the engine will flood. Is this hard? No. It is more of mechanical entity that needs TLC, thats all. It loves high revs and if not run hard it feels neglect. Its a gear heads dream. I hope this helps your understanding. Best.

Like Mark said it best and it seems like he has no personal knowledge of a Rotary engine. No sign of disrespect to him because I do own a RX7 and also driven a RX8 for a little while, and this is exactly the honest truth of the engine. Automatics does not do the Rotary engine any justice in fact they kind of harm the engines longevity because from time to time they DO NEED TO BE RED LINED!!! With the automatic the Computer will not let you go over 7800 RPM while red line is at 9000 RPM. The whole reason they need to be red lined is to clear up carbon build up on the Apex seals, the Rotor faces, and in the ports of the housings. So for that model I would personally pay no more than 7,000 Dollars due to wanting to swap in a Manual Transmission, pedal set, a new computer and other things to make the manual transmission work correctly.

I would not pay anything for a RX8... have the cooling system pressure tested and carefully inspect the engine compartment... These cars only overheat one time and then it is new engine time.