I had a Iveco daily lined with protecta kote a couple of years ago and it is now ready for re painting. That stuff only seems to work if you paint either directly to metal or have plylined the van out of one piece of wood, ie no joins. impossible in a big van of course.
 anyway just swapped vans for a transit lwb and came up with fibreglassing it. plyed the floor out, bought some 1" x 2" roofing latt and screwed it round the inside edges of the van. Made 2 50mm holes in the floor at the rear and slid some tubing down so any water that was in the van would run to the holes and down and out under the vehicle stopping it rotting. Had a roofing company come out and glass it all over the floor and up and onto the latt therefore making a seamless fully waterproof tray with 2 drainage holes moulded into it all. finished in dark grey with kiln dried sand included in the finishing paint layer (with hardener) to make a non slip surface. Works a treat and water just sits on the surface now until it drains away when i go up a hill! been told it will be bomb proof and any patches that need doing are a doddle with fibreglass repair kits off ebay .

 Anything to keep maintaince costs down must be good right?

Cool, any pics?

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For him to come out 160. Including all materials.

well only time will tell but it has to be better than that protecta kote rubbish! my old van had 3 coats and it still rotted the van. the only way i could see of protecting my new one was the tray idea with drain holes so that the water can literally only go down and out under the van. ps , the tubes are around 6inch long so they clear the chassis rail.