Very good deal! Go for it.
If you've never installed a top before be sure and do some research so you understand what you're getting into. See DIY here:
Pelican Technical Article: Boxster Convertible New Top - 986 / 987
I installed my Miata top myself and though it turned out well, I promised myself to never do a top again. Why? It wasn't nearly as easy or straight forward as the instructions implied. Clearance was very small and access from inside was extremely limited and it was awkward to work around the roll bar (guessing the same for the roll hoops in the Boxster). Getting the top taunt was not easy, seemed to be either too loose or too tight and adjustment wasn't quick or easy. In the end I got it done and it looks and works great, it was just a lot more work than I had expected.