Set your budget and stick to it,don't go over.
Find the fees out first as they can be really pricey,usually at least £100-150 on something like that around £1500.
Have a look at gumtree first though,I've seen stuff going through auctions lately thats going for more than you can buy it straight from the paper,plus of course you haggle down not up in there.
The auctions seem to be full of the public trying to make a few bob on stuff from there without really researching what sells although this is driving prices right up.