Have recently ( past 2 years ) seen some very pitiful MH,s getting repaired at my friend's workshop.
Will try to get some photos of the latest patient.
As BarryD stated, and from experience of my own Fiat Ducato, Alko rear chassis my first quest would be an Alko based vehicle.
Next desire would be to check if the vehicle had waterproofing treatment at birth.
In my case it did, and found it was then maintained by the original owner (met him earlier this year), hence most of the vehicle is in good'ish condition after 27yrs.
Typical areas that are prone for rust on a Fiat Ducato are:
Front cross member. This is secured by 3 bolts on each chassis leg.
The nuts also rust in chassis leg, so bolt spins.
Front Inner wings - various places. Typically inside above the fixing points of the brake pipes.
Also the top railing under the bonnet.
Battery tray, itself, and fixing bracket to the front wing.
Jacking points, the chassis rails to which these are welded to.
In past few years, on our 27 Yr old Ducato, 250k kms, noticeable are rubber mountings weakening, both general (water covers, mountings) and suspension bushes.
Wiring now becoming tired, Horn wiring needed to be repaired,
battery terminal connectors replaced, lights control malfunction.
Internally most still functions, have had failings in a tap lever, leaking rubber in shower, a few cupboard door securing latches.
Good luck in your search.
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