I paid around 1600 USD for everything. Counting the parts I reused from my old hackintosh, around 2000. A similarly specced Mac Pro 8-core is around 7200 USD.
thank you. A very useful contribution that neatly answers the question of why anyone would go through so much trouble. I would have guessed the difference in price was "only" a few hundred, and obviously would have been quite wrong! I never would have guessed 3.5 times!