Simon, Does that include everything? e.g. Winch wiring? switch's? isolator? Materials,tube, hardware and deck plate for tray and storage lockers? All the nice brackets to keep stuff stored? Materials for chassis mods? Uprated winch motors? all the little bits like heavy duty ARB lines? Palsma? etc etc etc! I only ask coz I recently had to do a breakdown of the cost of my tray back (which looks rough and very abused but has a decent spec) for the insurance company and pricing all the bits and materials at R.R.P's it came to a good bit more than your figures. I couldn't believe the amount all the small stuff added up to after I'd prices the larger items like winch's, ARB's, wheels etc
I have the same experience as Steve. My first truck I built ,2000-2001, I added everything along the build, and when I passed 20000 euro and the truck wasn't ready....

and that truck was a piece of junk....I That build was a budget build, not money wise in the end, but I at least I tried to make it cheap.On that time I reused allot of parts from the donor truck. What I found was the most expensive parts was all the small bits, like switches, electrical wiring, sheets of metal, some hydraulic stuff....These stuff I tend to forget when I make a build budget. So 15000 sterling including rebuilt engine, new/rebuilt autobox, electrics, stainless steel hoses, Earl's couplers, coolers, bodypaint, powdercoat, transport costs, tubes/cage, metal,welding gas, electric costs,grinding material, some parts made by external company, plus everything else included well that's impressive!
Put it this way, its very cheap. Yes its very cheap. I wished I gone that cheap way.... And the truck in my eyes, turned out very nice indeed.