I'm thinking about going with two 6 volt Deep Cycle Batteries this year. My 12 volt is about had it and want to build a plywood box and install two 6 volt batteries. Can anyone one advise me on where to get them (cheap), what size, how many amps, how long could I expect them to last in my unit, how to make a plywood box (pictures would be nice), is my stock charger good enough? Any and all advise would be helpful.

 

There is a post on the RV Net Forum about this.
Costco/Sams is where folks seem to get good deals on them. Golf Cart batts.

 

Costco is the place my dad got 2 deep cycle 6 volts. He has NO power problems on his camper.

 

You need to gather more info and learn about using deep cycle batteries .
All your question require spec.s , what are the batteries going to run , how long etc.

Here's link that should get you started .

http://www.windsun.com/Batteries/Battery_FAQ.htm

 

I did the switch 3 years ago I was going to buy trogen batteries (the best D/Cyc ) but went with the GC2 from sams ,there made by US batteries and have worked great and I paid $66 each . I installed 4 and with a trailer full of kids can run power for 1 week ,then I need to give them a full charge. Also do your self a BIG favor and buy a battery minder, when your tailer sits, un hook the house charger and use the Battery Minder, it will bring your batteries up to a 100% charge then go in to a desulfation mode . if you use the minder you wont have any more trouble with dead or sulfated batteries.I hooked mine up so when I get home I just need to turn a switch and then plug the minder in. just remember to un hook the minder when on the road because it will drain the batteries when not charging/desulfating.

 

There is also a plastic box which holds two of the 6 volt batteries end to end with a cover. Have one on my LQ horse trailer it holds two 6 volt golf cart batteries.