my grandparents are selling me one of their cars, its a 2010 prius with like 60k miles and im getting a really good deal, $6600.

I am really excited since its a great car and I want to use it for road trips since the back seats fold all the way down. anyone on here have experience with this and what should I know? any tips or tricks for making it more enjoyable?

I am planning to do a road trip around quebec in it, maybe not this fall cause it will be cold (although I guess I could just pack a lot of blankets). Also can I just run heat while sleeping or will it make the battery run out?

And is it safe to just park in any old grocery store lot and sleep? I assume it is in canada but maybe not USA...