Take a note that her 2000 SUV died. So the next one must be more reliable than that. No BMW or Mercedes. The best bet is to go with
1- Toyata 4Runner
You can get a very decent used one at $20K, lets see around 2004~5 with around 30~40K on the clock.
2- Honda Pilot
Same as the 4Runner.
Remember, she might not care about performance, tell her to buy something reliable that keeps troubles away. I had the 2003 4Runner for 4 years without any issue. Not even one visit to dealer for repair except for free oil changes I got for that many years. Trust me you can't go wrong with the 4Runner.

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2002 X5 3.0 Siena Red
Premium, Cold Weather, Rear Climate Packages, 19" Wheels
Aluminum Running Boards, Clear Tail Lights, Clear Side Markers
Titanium Kidney Grills, Titanium Trunk Lid, Xenon Headlights
4.6is X5 exhausts, 35% Tint, Aluminum Pedals
2005 530I Mystic Blue
Premium Package, Sport Package, Xenon Headlights
18" Sport Wheels, 35% Tint all around
Mods to come: M-Tech Front Bumper, M5 Side Skirts, M5 Rear Bumper
Quad Exhausts, Style 172 19" Wheels