You just said "diesel". In here that means people will be telling you to run away from that car ASAP ;-)

The diesels got a bad rep in the States. I believe mechanics unfamiliar with the diesel engine and general lousy maintenance are to blame. In all fairness I should add that these engines are pretty unforgiving. You have to treat them right (and remember broken timing belt = byebye valves).

Around here (Belgium, 55-60% of new cars are diesels, been so since decades) there are quite a few D24's (the engine type) driving around. Most mechanics (both indie and dealer) are quite experienced with diesel engines.
Around here the D24 is known as a pretty decent engine. Sure it lacks the power modern diesels got (hello, introduced in '79!), but they still get around nicely (you won't be winning any stoplight-sprints though). And with frequent and religious maintenance (and proper driving habits of course) the engine will serve for a long time, albeit never as bulletproof an engine as the redblocks.

My D24 240 sedan has currently got 255000 kilometres, uses no oil between (3000mile) intervals , mileage is 6.5 litres per 100 Kilometres (I'll let you do the math). Top speed is about 150 Km/H (GPS), cruising around at 120-130 is easy. Never had it overheat on me (and I've done my share of mountains) either.

I guess the real question is: can you find a decent diesel mechanic or are you confident you can master it yourself.
[If the latter you'll need the books and tools to do the timing belts (front and back).]

Good luck
--
'92 Volvo 240GL 6cyl. Diesel