I wouldn't play the time game. I mean, if she was just dictating the when/where with NO notice I see it, and that's fair. But if you two have a previously agreed upon time/location that is mutually agreeable I don't think that's the right place for what you're trying to make a "power move".
The dressing nice, validating, 2 cars and not making it overly long are all good pieces IMO. You're part of the conversation too, so if you feel it's really getting dragged on and you're not making progress you can say, "I think we've both covered some important topics here, and I'm not sure that at this point we have anything else to add. Let's call it a day for now". You should let her do most of the talking, but you do have some control of the meeting and its duration.
