Tell me about it. I'm in a similar boat. My audi a4 has had a parasitic draw for the past 10 years. My mechanic didn't want to take the time to address it because that sort of thing takes a serious amount of time and he's always backed up. I got out my fluke and narrowed the cause to what I believe is the comfort control unit. I can't replace it myself because it's a coded part. My mechanic won't do it because he won't confirm that's the cause.
None of the other mechanics in my area have the equipment. Even the Audi dealership won't touch it because they're backed up too. So, I keep a battery jumper in the glove box and hook the battery up to a tender when I can (outdoor parking).
I don't know what I'm going to do for my next car. Pretty much every car made after 2010 has coded parts and are more computer than mechanical. It does make me tempted to learn the electronics part and open a garage that focuses specifically on fixing electronic issues in modern cars.