Originally Posted by Adam

They usually take your used engine, as mentioned earlier. 10-15k is way high for even a slightly used boxster engine. They probably sell it on the aftermarket like you want to. You may get 3-5 k for a slightly used 2.7L or 3.2L engine. There was a nice 3.6L 996 engine with less than 5 thousand miles on it on ebay a few months back for 5.5k. I'd be happy with a 3.6L boxster with 320 or so hp. Any car with a power to weight ratio of 10hp to 1lb or greater is pretty fast.