We're planning to return an Enterprise rental (from a pickup in Southampton) on a Saturday in May at LHR, for an international flight on BA, out of terminal 5 at 16:00.

There are 3 regular Enterprise locations at/outside LHR, but only the one noted as "in terminal" is shown open past noon on Saturday. Several questions:

1) Is that lot location truly "in terminal" or just the out-of-terminal car lot for terminals 1-3 reservations. and truly available for dropoff, also?

2) Will they shuttle you to terminal 5 from the lot, or just to terminal 1 and let you make your own way over to 5?

3) If you changed your mind, could you drop off at any of the 3 Heathrow Enterprise locations besides the one you initially reserved? (There's no difference in rental price)

4) Do the other 2 locations (Hounslow, Bedfont) shuttle to whichever terminal you wish?

Reason for all the questions is we'd like not to be pressed to have the car back before noon, but have had horrific experiences transiting Heathrow in the past, so would like to at least start at the terminal we fly out of. (It once took us nearly 4 hours from arrival at LHR to our boarding gate)

Thanks, all!