new here and have a question

Today I found out my insurance covers bariatric services when I originally thought they didn't so that was happy news! My doctor told me I needed to call and find out co-pays and that type of stuff to find out what my financial responsibility would be. I called (I have United Healthcare) and they told me there is a $20,000 lifetime max for this surgery. I know I've read a question about this on here before (I've been lurking for awhile), but was if anyone here has dealt with that and wondered about how much you had to pay out of pocket if. I know all surgery costs are different, but I'm just curious since my doctor's office is closed for the day.