Mine is 13' X 11'
In there is a 400 litre processor, 800 litre oil settling tank, 205 litre drum of methanol, roll along tool chest, stainless catering table, sink unit, dishwasher, pump and filter setup for my fuel dispensing nozzle, loads of shelving and a huge collection of plumbing and electrical bits.
On the rack under the catering table are a trolley jack, axle stands, mig welder, grinders and assorted large tools.
Outside is a 1400litre finished biodiesel storage tank