RE: Starter Battery
J-
I agree with Mike. The problem you run into is down the road when you want to put together a field box. I started with a motorcycle battery and an electric starter. Later on I got a field box. The motorcycle battery was barely too big for the field box. I ended up having to get a gel cel hobby-type battery. If I were you, I would go ahead and get the hobby battery now. It is about the same price.
-Scott