I've purchased 3 911s on eBay:
A project consisting of a '69 RSR-look, 3.0 and 915
A high-mile, straight, unrusted '72 coupe
A non-running '73 coupe
They all were $4-5K. They all turned out to be worthwhile investments.
The rule of thumb on eBay is to hold back 15-20% of value if you haven't seen the car. Pictures reveal a lot, but sometimes the owners themselves are uninformed or devious (Imagine my surprise when the "sunroof" in the '73 turned out to be hinged glass!).
