[AllHailKingVolvo]

I have to agree with Dave here, unless you want to spend major money on a cherished or recommissioned car, it’s unavoidable that as any 9/700 series is going to be at least 20yrs old, most are going to need some work.

It sounds like your current 940 isn’t a million miles off, personally I’d change the engine and gearbox mounts as a first port of call for the vibration. Could the diff be a potential culprit too? Worth cracking open the filler bung and checking if it needs some juice.

Sump wise, I’d get it in the air and drop the sump out (changing the O rings in the oil pump whilst I was at it) and replace it with one from a breaker. Faffing about with no drain plug sounds like a nightmare.

Air con is sortable relatively inexpensively, as are the indicator/headlight issues.

I’d keep it, spend the money it needs and make it as up together as possible. That’s the approach I've taken with my 744, and although it hasn’t been a cheap undertaking, it’s a great project and it’s “my” car, as it were.

You could keep buying, fixing and flipping cars all year long looking for the “right” 940, but even that will have bits that need to be sorted and the odd issue that needs ironing out.