Currently, there's no independent repair shops to compete and bring repair costs down, so I have purchased extended warranty for both my 2012 Model S and 2017 Model X.
My 2012 Model S suffered a $4,000 repair for MCU (17" display module) at 60,000 miles. Notice that if you don't need to replace the whole MCU but only the screen, it is much cheaper.
At 80,000 miles it suffered a $4,500 repair for cabin heater.
It's not a lemon car but for 2 repairs that are worth $8,500, it's just crazy!
Since I bought the extended warranty, I am way ahead!
It's just like healthcare insurance: Most people are healthy but if they suffer a cancer or 2, it's unimaginably very expensive if they don't have coverage!