How long would I be able to be out fishing in one of these with just a trolling motor? And are there things that you can have on board to keep your battery charged if it were to die? I am thinking about buying one here in the next couple months and was just wondering if I would need to get a small outboard to go with it. Don't want to spend that kind of money if I don't have to. Also, would I be able to take it out on a good sized lake?