Definately worth a good luck over. Don't forget to print off the buyers guide and go over every inch of the car. Pull the carpets up, get under it, and if you decide it's the one then do a quick HPI check over the phone or internet before you hand over the cash.

I usually ask if there is any problem with history, if they say no, then I say "OK, here's a hundred quid deposit - refundable only if the HPI check is bad" - and get a receipt for the deposit that states that.

That way you secure the car, and have a get out clause if it's a wrong-un.