As posted elsewhere ( "What cheered you up" threads ), I was informed that the 'van might not be too bad, and yesterday, Karl and I managed to get to Norfolk to check it out.
Damage is very minor, virtually non-existent, with just a thin layer of mud dust on the floor from the muddy water. The laminate flooring is intact, with no lifting or other damage, and there's no signs of rising damp in the walls or wooden doors and cabinets etc. All seating and soft furnishings are fine, with just a very light dusting of dry mould here and there, from the damp air / condensation, which should very easily clean off.
The interior is dry and no odours of damp or rot, and will easily clean, and the outside just needs washing down with a jet wash, to remove the green patina left mainly on the roof, from the overhanging trees.
We didn't test the electrics, but as the supply consumer unit, and most, if not all wiring is above the level of where the water invaded, which we reckon was only just over the floor, coming in under the entrance door, it should be fine, and all appears to be dry and undamaged.
Hoping to get down there again in the near future, and get it all sorted and up and running, and I'll "report back" then.
Pic below, from Karl's 'phone, shows the rear end of the 'van interior, with the blue hose being the "Whale" pump for the external water supply, left inside when the van is not in use, and the camping chair and table under the rear seating area.
The dirty floor can be clearly seen and, when the dust is moved, the floor beneath is actually clean and still shiny.