Buying our 85D was just a matter of sitting down with the rep at a Mac in-store and ordering from TeslaMotors.com. The most painless car buying experience I've ever had. We could have done it from our house if we wanted to.
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I should add that we've done the whole "pit 2-3 dealerships against each other over email with exact spec" before and while it does get you a good deal, it takes a ton of time and requires you to be willing to walk away and waste an evening if they pull any funny business.