Feedback looks like something to worry about, but if I was serious about buying it, I'd arrange to see the car in the flesh and check the guy out too. And for that money, a HPI check would be a good idea.
Mind you, a quick RFL check on the DVLA's website ties up a few things - it's listed as black with a 1.6 engine, and the tax expired on 11th August. Might be okay. If you're not sure what website I'm talking about, click here to have a look and click on "Vehicle Enquiry" - you simply enter the registration and the vehicle make. It's not as good as HPI, but a good first step IMO!