You do get the odd bargain - when I was looking for mine I did miss out on a genuine one on fleaBay for less than £14K fully loaded with under 100K on the clock but they're pretty rare (generally seems to be personal issues forcing a quick sale type thing) - if he's got time then he'll generally get a better deal buying a decent base vehicle and doing it himself - don't expect much change from £8 - 10K tho if you're looking for windows, poptop, crash tested R&R bed, insulating, electrics, swivel seats, heater, units, fridge, DAB, yadda yadda yadda....... I spent pretty much the whole summer on mine too!
Don't get me started on what it can cost if you want to pimp the outside too
Oh and generally be wary of offers that appear too good to be true as there are a lot of scammers out there, especially on fleaBay and scumtree...
:D