I bought mine second hand on ebay. I can see the advantages of buying a new one, but have enjoyed bringing mine up to scratch :thumb:
I've kitted out the inside with an old unit that I modified to fit around their existing bedroom, which is a free standing wooden box/hideaway. I've bought an offcut of hard wearing, non-slip lino for the floor (£7!) and am planning to insulate the walls. It's slow going but worth it!