we all feel for the OP.
but as I said in my previous post vans are repairable if you are prepared to do them, kind of reminds me of the old wreck we bought years ago. started with a little 3 berth and with a growing family wanted something a little bigger. looking round the dealers I spotted a 5berth fleetwood colchester sat in one corner, when I asked about it the salesman said it was not for sale as it had extensive damp at the front they were waiting for a scrapper to collect it FOC but I still liked the look of it and it didn't seem that bad, on impulse I offered him £50 for it. he accepted and I took it away same day even gave us £250 for the little van.
armed with the remaining £200 I set about the van stripping out the front of the van is was bad but the frame was suprisingly solid just one rotten piece that was replaced, you could see where the water had got in so it was resealed on the outside as well as inside, new wall boards and section of floor fitted window seal and new carpet.
kept that van 7years never leaked again. when I sold it to get the motorhome the new owner was happy about the repair and even though the van was now over 20years old was bone dry. they kept that van a further 10 years after that on a seasonal pitch and never reported any issues, If there had been I would have known as I sold it to the BIL.
thats a full 17years after it was going to the scrapyard.
old vans can be repaired if you are prepared to do them. just because a van repairer says it too far gone does not mean it is !!!!