[thstone]

Two of my friends bought dismantler/eBay engines for $4K and swapped them in. Everyone lived happily ever after. Of course, eventually the engines will fail and then they'll swap in another used engine.

Boxster engines are becoming disposable - its not worth putting $12K-$15K into an engine rebuild for a car that will be worth $10K when you're done.

Of course, its your money, spend it however you like, but you'll be hard pressed to recover a majority of the cost of a rebuild upon resale.