I've anecdotally done some research and in SoCal a true concierge medicine for what I would be looking for with a brick-and-mortar location and imaging on-site is ~$5000/yr.
One of the huge benefits for me has been that I have much simpler access to specialists. They are somehow able to punch through a lot of the scheduling bullshit for me, so when I do need to see a specialist, I am not waiting for weeks or months; Sometimes I've been able to get appointments at a specialist through them within a few days instead of the few weeks it would have been had I tried doing the same myself.