Just for the record, you can fit two snowboards in the back seat. Each board has one edge on the floor behind the front seats (one each side) and goes diagnoally up over the rear seat, it works, trust me I've done it and roof racks are for girls >.<
aA for the actual topic, I bought a very clean stock S2 and have done the mods myself, I'm a hands on person and enjoy seeing the car take shape. Plus you really know the difference when you drive iti nto the shed, do something then drive out and the car has a new personality, it's very rewarding, more expsensive yes but very rewarding. I also agree with the comment that you're more likely to find a stocker in better condition. Just my 2 cents.
Good luck =D