I think I might have been in a similar position to the OP when I bought my first X5 in 2018, a 2002 with just over 20k on the clock.

At the time, I needed to buy a car for my business, but didn't want the cost, depreciation, or truthfully all of the automated features of a new car. I wanted something that for the most part I could maintain myself.

I was certainly not unfamiliar with the ongoing maintenance costs of an aging BMW but the asking price and condition of the particular car I was looking at made it seem like a worthwhile gamble. I knew what I was getting into to some extent, having previously owned a 2006 X3 (bought new) with the same M54 engine. It was super reliable right up until the time I sold it at around 167K. In retrospect, I wish I had kept that car for my son to learn to drive with, but I was out of garage space. In a perfect world I would have just built a bigger garage. :-)

Another factor for me was that the the GVWR of the X5 put it just over the threshold for the Section 179 "Heavy" vehicles that allowed a 100% bonus depreciation in the first year. Can't beat that!

My wife liked the car so much that early the next year when we happened to find a one-owner 05 X5 3.0 being traded in at the local dealership with under 19K on the clock (!), we snapped that one up and haven't looked back. So for better or worse, we've now got two of them in the garage for less than half the price of, say, a new Honda Pilot.

Even with the ongoing maintenance costs, those numbers are working for me so far, and I plan to keep the X5s as long as I can continue affording the maintenance costs. And the cost of filling the darn tanks.

Chris