All the rental car suppliers were moved out of the station at the start of the year. Most now are less than 2 miles away from the Rail Way station. The way to FILTER and discover this:-
On the search results page, where car photos are displayed, at the top right hand side, select from the drop-down list SORT BY DISTANCE.
Bath is a very small city, and there are planty of cabs directly outside ($10). Also, most suppliers will come and collect you if you call them as you are approaching the station (say 45 mins). The details of this will be contained within the email confirmation voucher you will receive when completing the booking online.
Also it costs extra to rent a car with a GPS and do all the cars have usb ports?
Those are contained under EXTRAS, you reserve online and pay on arrival. The high-end vehicles may have factory fitted ones. All cars have USB.