rent vs hire??

[Mandalin]

One can do both with a rental car, no?

But otherwise what are the rules with these words? Is it just a matter of collocation?

I've never looked it up, but my personal feeling would be that you rent something for a prolonged period but hire it for a single use.

I would assume a rental car had a contract for a year or longer, and a hired car was for a week-long holiday.

Doesn't help you but Americans don't really use the term hire. You rent everything for any amount of time.

Very true. Whereas in British English, boys are the only thing you rent for a short time.