aczlan
Good Morning!
\My folks have 3 XC90s, a pair of '05s (one is for their vacation property) the other is a '13, I think. The '05s are turbo I5s, the '13 is a NA I6. All AWD, all well over 100K miles, one of the '05s is pushing 250K miles. They bought the '13 used to replace the higher mileage '05, but knew it wasn't worth the effort to try and sell it, so it's been part of the "farm fleet" for 3 or 4 years now, and still going strong.
Yeah, the AWD can be problematic, but it's not hard to fix, usually the coupler between the trans and the angle gear (transfer case) strips. A competent shade tree mechanic can fix, Youtube & FCP Euro are your friends.
Whiteblocks will run forever, change the oil, and don't forget the timing belt every ~100K miles/5 years.
As others have stated, avoid the V8 and the T6, you'll be fine.
Also, use synthetic oil, not dino. It holds up better and causes less sludge in the PCV system.
See: https://www.robdiesel.com/wordpress/2016/05/p2-volvo-v70-and-s60-buyers-guide/ for some things to look at, a lot of things cross over from the wagons to the XC90.
Aaron Z