Are you trying to buy new or open to slightly used?
I had a '05 Cayenne Turbo and LOVED the thing. Will definitely get another one at some point. With a tune, IPD plenum, diverter valves, intake, bypass pipe and exhaust it was an absolute rocket. I think 575 hp after all that or something?
What I loved about the 04-06 Cayenne is that they were PROPER SUV's. Trick, diffs and offroad tech, incredibly capable off-road and on. Inside really nice as with all the typical Porsche touches and I loved the alcantara roof. IMO they still don't look too dated. I know you can easily pick up a 50k mile '05'ish for mid 20's. Buy an aftermarket warranty and you're good.
Awesome, awesome trucks.
This was mine. Sounded wicked. Loud but not intrusive inside.