Please help with New Battery Purchase

WE have had good luck with the Duracell brand from Sams Club. They are 6 volt wet cell, so you have to watch the water. If you are going to be plugged in for long periods, make sure your charging system is a good quality battery maintainer type charger. As far as time, we have been out a good 3-5 days boon docking and never have had to worry about charging them. We do go in cold weather and run the heater during the night with no issues. Your batteries will last as long as they can under your usage needs. We really don't use ours much during the day except for the water pump and fridge. Under strict management we have gone 5 days with power to spare.

Definitely go with 6 volts. You wont regret it.