Hi all, new guy here. I have a 1993 Volvo 850, a few points. First off, it's not a lame Ford motor. The 850 and the 5 cylinder white motor were designed way before Ford's purchased of Volvo. Volvo was looking to build a more modern sports oriented sedan, and that meant front wheel drive. They were counting on the 850 series to completely change the publics perception of Volvo from one of stogey conservativeness to a more sporting, performance oriented one. I think the 850, especially the turbo models, did that in spades.
Now to the 850 specifics. If you're looking for one, I'd go with the 95 or 96, the least amount of problems with those models. Definetely go with a turbo, the N/A cars are seriosuly underpowered and the turbo also helps keep resale value a little higher. My car is N/A (they did not offer the turbo option till 94) and it's a dog, one of the few complaints I have about it. Transmission problems exist for all years of the 850 for one simple reason, Volvo themselves. They tried to bill the 850 as a "low maintenance" car, and specificed that the automatic transmission fluid was good for the life of the vehicle. Hello, it's the same fluid that everyone else was using. Anyway, because of that most dealer serviced vehicles never got a trans fluid change, and transmissions end up dying somewhere between 100K and 150K. If you can find a car that was owned by someone who changed the fluid regularly then you'll have no problems with the trans. However, if you're looking at a car that has 130K on the clock and you can find no evidence (through records) that the fluid has ever been changed, I'd walk away or get them to come way down on their price. Incidentally, a trans swap or rebuild will run you somewhere between $2500 and $3K. Fortunately, my car only has 90K on it when I got it. The fluid had never been changed, so I did it right away. I think I caught it before any damage was done. Other sore points on these cars, rear main seals. The 850 motor does not use a PCV valve, it has something called a flame trap. The flame trap needs to be cleaned regularly, if not it will clog up with gunk. If that happends crankcase pressure has no where to go and the pressure buildup will cause seals to pop and start leaking, most notably the RMS. That job will run you about $1K to $1200, and it is an extremely difficult DIY job. The ABS controllers go on these cars to, and thats a simple 10 minute job to replace, but the part itself is about $800. Front sway bar end links go quickly, causing clunks in the front end. Motor mounts go fairly regularly, causing yet more clunks and vibrations. If you want to read up on some thing try this place:
https://brickboard.com/
The best Volvo forum I've found on the web. Don't get me wrong, I think the 850's are fantastic cars and I love mine, but they are not cheap to maintain. No Camry or Accord bullet proof drivetrains here, but tons more style and performance (with the turbo). I do mostly all my own work on this car, so PM me if you have specific questions and I'll try to help if I can.
Good luck.