Unless you get one 2nd hand mate, a Hottop is going to cost you £500. Since they've only just come to the European market and only a very, very small number of folk had one before then, they just aren't on the 2nd hand market AFAIK. Even if the European distributor were to cut you some sort of deal (and I know of no reason why he would) you're still looking at the thick end of £500.
So you either look out on eBay until a used Alp comes up, or you build a barbecue roaster.
I'd never really thought the barbecue roaster an option in our climate, but MattS uses one regularly and he lives in Glasgow. There's lots of info about how to build one on
www.homeroaster.com (not to be confused with homeroaster.co.uk, a very different site!
). Also Matt has promised me an article on barbecue roasters. Expect this sometime in mid-November as long as Matt's domestic pressures allow.