Being that I am ordering my S85 in a few weeks I have a question too.
To what extent can normal auto mechanics work on this car? Can they replace the brake pads?
Yes.
Can they replace the tires?
Yes, many of us have switched from summer to winter tires; any normal shop can remove and replace the wheels, remove and remount the tires, it's all standard enough.
You need to have the correct tire pressure rating (which is really unusual, but is right there in the front doorframe) and the torque rating for the bolts (which is also really unusual, and ISN'T listed -- I always phone Tesla to get it).
You need to show the shop where the mounting points for lifting the car are so they don't hit the battery with their jack.
You need to puit the car into "jack mode" before they lift it, and they'll appreciate it if you also put it into "very high".
Can they replace the brake fluid?
Discouraged. (How often do you replace brake fluid? I've never replaced it on any car unless something went seriously wrong.) I think it would be possible in an emergency, once you know how to disassamble the plastic in the frunk; I've seen the brake fluid reservoir after a bunch of the front end plastic was disassembled for something, and it seems straightforward enough.
Yes. (The hydraulic brakes will still work if the power systems die.)
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Another noob question: Seems like standard tire rotation is recommended ~every 5K miles. I used to just get it done every other oil change on my ICE car, but no more oil changes. What are people doing in terms of tire rotation? Where are you trusting tire rotation to? I drive 35K miles/year so thats a rotation every other month or so...
Thanks.
Yow. I drive much, much less than you, so I just rotate the tires when I switch from summer to winter or back.
....actually, I'm not even sure whether I rotate them or not. Because they get stored for six months without labels as to which wheel they came from, they probably get put back on at random.