Ryan,
Just to make sure you don't fry anything expensive, you'll need a 24 volt trolling motor to run a 24 volt system. If you have a 12 volt motor, you can still hook two batteries together (parallel) to make 12 volts with double the run time.

As far as maintenance, I fish a lot (not this year, but other years I have). During the summer I would usually get out 3-4 times per week, sometimes more. I almost always charge the batteries after each outing, and really try to make sure they get a full charge before taking them off the charger.

With my 24 volt system of two batteries, I got great life out of them. They were a year different in age. I got 6 years out of one of them, before it wouldn't hold a good charge when it got cold out last fall. The other was 5 years, and was still doing decent at the beginning of this year, but I figured I had better get two new batteries so they were equal.

I consider that great battery life for typical lead acid batteries. These were two 27 series Napa batteries. Now Napa has changed manufacturers for their new batteries. I've heard mixed reviews on the new ones. I'll have to see how they hold up.

Also important to run life is battery size. Get the biggest battery(s) that you can fit in your boat. I have been using 27 size/series, but should really see if 29's would fit when I have to get batteries again.

Good luck!

curleytail