Top work!
A neighbour spent months buttering up the local planning committe using genuine graft, then built a 2 storey extension, using his extended family to do the build. I suspect it cost no more that 25% of what I paid. It took him 9 months to complete, though, and is a bit chavtastic...
Ours is 5 by 4.5 (with an exquisite patio of similar dimensions part of the build). Everything (architect, planning, skips, portaloo (ffs), kitchen (top schmutter), bathroom (top schmutter), fittings, fixtures, three separate circuits of underfloor heating, 7 triple glazed roof lights (3 of them...