I had a Passat V6 years back. Was a blast to drive.
Then one day the thermostat went bad. Brought it to a mechanic I know well and he said "You should probably take it to the dealer. I can't see any way to get at it except removing much of the front end, the timing belt, and a bunch of other stuff. If I do it, it's going to cost you $1500 to replace a cheap part. They must have a way to do it a lot easier."
I went to a dealer and they told me the same and wanted $2000 to fix it. For a cheap thermostat.
I got rid of the car the next week. Loved that car, but didn't want to deal with that.