When does one surrender and sell the van?

We have had the van from new and in addition to van and conversion service charges plus road tax, MOT and insurance we have replaced;
the fridge, the toilet compartment door, the front skylight, the tyres, the radiator and had the air conditioning unit and the toilet skylight resealed. 
Recently another van damaged a wing mirror, the fridge door latch spring broke for the second time [replaced with a safety pin] replaced a reading light bulb, I have still to resolve the problem of the heating switch control panel being pushed out of place,[anyone know how to remove the fascia to get get at this?] repainted the awning end caps and on cleaning out the drain tube at the end of the windscreen scuttle the grey part that one can see from the top parted company with the tube.
Now it would appear that we will need a replacement to the silencer element of the exhaust and the underslung gas tank would appear to be badly rusted and will need repainting or replacing. 
We cannot afford to replace the van but it is costing us on average £1500 a year and the costs seem to be increasing quickly as it gets older.
We haven't even been able to get away this year due to covid issues. Age, asthma and high blood pressure, which just seems to get worse with each new problem. Despite all the good times it does seem to be becoming too much of a worry. All this and I am not old enough to get my pension yet!

If you have read all of this I thank you and any help with the fascia panel and gas tank would be really appreciated.

We're in the same position - we haven't been away in the van since last October, and don't expect to this year at all. I don't think there's much you can do other than accept that these are exceptional times and that they will pass.

You don't say what year your van is in your forum profile but, to be honest, £1500 a year to keep something as complicated as a motorhome running doesn't seem that unusual. When you think about the depreciation that you suffer on a brand new van - which with a high spec model could amount to almost £10,000 a year, it doesn't seem all that much. I can recall adding up all of the maintenance costs on the last van that I owned (for 10 years) and that was around £1000/year, including depreciation - which I though was excellent! But some years (e.g. the one when it was welded and painted) it was a lot more than £1500.

The fascia panel: you'll probably get more useful replies if you say what year the van is, and what fascia you mean. I would guess you probably mean the heater in the cab dash, rather than the heating system in the back of the vehicle, but I'm not sure.

The piece that I have pushed out of place is the small section that houses the heater control switches and the van air condition switch on 2011 Boxer van. Everything still works but it does need sorting and I expect that a main dealer on hourly rates will be very expensive.