Its not some ordinary steel box sheetmetal thing someone threw together bro. If it were steel it would weigh a fucking ton, this is all made of powder coated medical grade ALUMINUM. 2 people can easily lift this thing up and down stairs and through doorways. It has high grade rubber coasters on the bottom so on a flat level its a cinch to move around. Has a CO2 system that is already engineered to keep 1500-1600 PPM levels. Ventilation system and carbon scrubber all built in.
You could not possibly even begin to build this box for $150, that would only be enough to get the fans. You could MAYBE build it for $2000 yourself if you got all the parts at wholesale prices and did not figure in your labor as part of the cost.
Woomeister you might want to do a little research before you open your mouth next time, you cannot get this in the UK for $400. You might be able to get a big heavy metal box for $400, but it certainly will not contain any of the parts therein. You still need ventilation, glass, hoods, reflectors, 2x 400 W digital lumatek ballasts, CO2 controller, keyed locks, Bulbs, Water Pumps, Air Pumps, Medium, Net Pots, PH pens,TDS pen, Nutes for a year, CO2 regulator, Carbon scrubber filter, Programmable Logic Controller, powder coating finish, plus all the engineering and testing that went into this. Hardly possible for $400.