Fresh Water Pump
The Frugal Choice: Milescraft 1314 Drill Pump
If you carry a drill with you anyway, a lot of RVers are completely content using this clever little pump.
Your First Upgrade: Bayite 12V Fresh Water Pump
Some people wire this into a power point (cigar lighter) pigtail adapter and plug it into either their vehicle or one of the DC outlets in their RV. Others wire it into a trailer lights pigtail adapter and plug it straight into their trailer lights plug on their tow vehicle.
The Savvy Sweet Setup: Wayne PC4 Water Pump
It plugs straight into either your generator or any outlet on your RV. Tidy looking case. Made in the USA. The Wayne brand has a stellar reputation. The main caveat with this one is that you have to pour a little water in the top of it before starting it (priming the pump).