It took me a few posts to realize this was a thread from Nov 2017...
Anyway, I am someone who cannot plug in at home currently, I live in a New York Apt building with no charging access, so when I first got my M3 I was obsessed with vampire drain and checked it every few hours. It's kind of ironic that the more people do to monitor this, the more drain you suffer from. In the early days people were congratulating themselves for installing TeslaFi to monitor the mysterious drain, and yet for many it was actually TeslaFi that was causing the issue. The fact that people still think TeslaFi's new features "put the car to sleep" rather than just not messing with the car's built-in energy conservation features, is testament to how you can create more problems for yourself by being overly-vigilant.
The car is pretty resilient to what it considers normal use, and it's also worth noting that most of the major 'drain' occurs in the first 24 hours of parking, which is a result of the battery cooling significantly, and the car taking time to go into a deep sleep and communicating with Tesla. It's also worth noting (in my experience this is true at least) that the car will often report a lower charge than it really has when the battery is very cold. I've had times when I've gained 1 - 2% of battery charge in the first 5 minutes of driving, despite Whr-useage in the 800's when first setting off.
I rarely use my car during the week, so on Sunday evening I'll often park up with anywhere between 60 and 85% charge (last night I came home with 87% charge) and when I'm ready to head off for a weekend retreat on Friday or Saturday, it's usually lost 3 - 4 % for the week over 5 days.
I would give two pieces of advice to new owners:
1) Change the settings to display state of charge in per-cent (%) rather than range. Psychologically 'range' messes with you as it's far too dynamic, making you paranoid when you see your car lose 2 or 3 miles of range before you've even gone half a mile to the highway. This isn't unique to EV's - my Golf GTI would show 'range' anywhere from 480 miles to 270 miles on a full tank, depending on how I'd driven the last 10 miles.
2) Let the car's energy management systems do what they're supposed to do - i.e. don't install 3rd party apps. I know that's an unpopular statement, but battery technology by its very nature is imprecise and you'll likely spend far too much time fretting about why you lost an extra 3 watt-hours last night, compared to the prior night. I'm also a geek and would love to know every last detail, but I also know that will make me want to micro-manage the car, and it will cause me anxiety. I'm not arrogant enough to think I know better than Tesla's engineers.