KlausC gives great advice,

My dealer used to do a Volvo certified used car check for one hour's labor, a second hour for a compression check. If the car had no major issues, I would have them put new plugs in after the compression check if the plugs were suspicious at all.

I would get a written checklist - they can tell you if an ant ever farted in the trunk!

Two and a half years ago, I purchased a 2008 XC70 - I had NO repairs for 2 years after the seller ( a dealer ) repaired the brake pads and vacuum pump.

I figure that repairs cost - Volvo dollars - no matter how pretty it is, needed repairs on a used Volvo purchase can easily cost more than a 16 year old car.

If the s60 has a 4 speed gear box, you can use Mobil 1 ATF, synthetic. A 5 speed uses Toyota 3309. But get any updates for the tranny first, dealer only. While there you could opt for a vehicle inspection, usually 1 hour labor.

Look at Volvo's web site and plug in the VIN and see if there are any recalls.

I doubt that the ETM was replaced at 44K, the free replacement lasted until 2011. They usually were good until 60K miles or so. The problem is finding a replacement with a white sticker that doesn't have 180K+ miles on it. Dealer is quite expensive.

Change all of the fluids! Do her a favor and replace all the brake pads, especially the rear. The rotors should be good to go.

Timing belt is over 10 years old, the belt and tensioner are replaced as a pair. The H2O pump should be good.
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Keeping it running is better than buying new

Check to see if the ETM has already been replaced. Maybe it has? Look for a sticker.

The best thing you can do for the tranny is to get a software update. Changing ATF certainly wouldn't hurt but make sure you use Volvo ATF.

The 2001 cars aren't necessarily a lost cause. A friend of mine has a 2001 V70T with almost 200K and zero tranny issues. Not all the 1999-2002 Volvos have the tranny problems.