Dear P Just got back from holiday. My builder installs logs cabins - they can be small ie. 3m x 3m would only be about ?1,500 to buy, but you would need to put down a base and it sounds like you go do with some electrics - which is where my builder comes in as he can do both. I've got a 5m x 5m in my garden which has roof, base and wall insulation and double-glazed windows and doors. Probably a bit bigger than you would want but it would serve as a good example of what you could get for not much money. Also - provided it doesn't take up more than 50% of your garden, you leave 1m boundary all around and it isn't higher than 4m - then you don't need planning permission because it's classed as a non-permanent structure. If you're interested in more info - viewing my log cabin then contact me.