I have nearly finished my DIY filtration unit, I have yet to add the power switch but otherwise its pretty much complete. I was shocked at the price of these things, starting at about £1200! So I decided to build one out of parts I already had. I did have to buy the lift pump, which cost £150, and the 10 micron filtration unit at £25 plus carious hydraulic fittings probably another £25. The fold-up pallet truck I found in a skip. The 24V 12A supply I already had. The unit works really well and doubles as a 20l drum carrier. In fact the drum is needed as the pump and filter tend to be rear heavy!