"Cheap" batteries?
Unless you like unpleasant surprises, I think you might want to consider saving money on something else and put those savings into the batteries. Cheap batteries die unexpected deaths at worst possible moments, but, hey, it's your boat...and your stranding!!The golf cart battery argument is pretty valid, but there's something you need to think about; what's your charging source? If you go out, use the batts overnight a night or two to run the house (not start the engine) and then come back and plug into shorepower for the recharge, you'll probably do ok. However, you better have some real muscle in your alternator(s) to charge them puppies back up after putting any length of time on them. Remember, what you take out, you must put back and the more you take, the longer it takes to put back if you have undersized charging capability.Just some thoughts. Good luck.