Why not take your time, check Ebay/ Autotrader everyday for a few months, get loads of advice off the guru's on here, then when your sure you've got a bargain, take out a private warranty and save loads!
mate,thats a top idea,i've had a look about,and have found 3 "large" companys that offer this,and im tending to lean towards this one...... http://www.click4war...ranties-uk.aspx
any thoughts,or any other companys i should be looking at?