I had a look back at my history, and honestly the only actual "problems" I've ever really had with my X5 was the drivers door actuator, one window regulator, trunk actuator, and two transmission issues.
Everything else would be regular maintenance items that should be changed regularly/normally. CV boots twice, self leveling bags once alternator once, brakes linings, one pink xenon bulb, one fog light bulb, many rear bulbs, two radiators and a reservoir, one ruptured upper rad hose that I fixed on the side of the road (at 130,000 miles my fault because I had been through two radiators at that point, but only changed the belts/hoses once and the dealer didn't give any insight when they replaced gaskets and radiators) suspension bushings once, passenger side seat control (I fixed myself) one fuse 48 HVAC control replacement, one valley pan and a few other engine gaskets. I've had those issues, but they have to be there. There are a few more not listed. I had one "issue" where the dealer left a fuel line detached and the vehicle stalled on the road.
I won't really count that because I found the issue after a day of searching. I almost gave up and returned it to the dealer, but they would have lied about it.
You have to expect more issues the older the vehicle gets, but if you're getting your maintenance done at timed intervals, problems should happen less frequently. Every vehicle WILL have issues when maintenance is neglected, and hopefully the OP understands that.