Go to a Ag supply store near you and buy a tractor battery. Will last for many years, we can get them around here for about $50.
That is correct. If your car starts easily a deep cycle battery is only tickled and no harm is done. If you have to crank and crank you'll be glad you have a deep cycle one. If you are comparing quality just pick up a T-105 and you will know for sure.I've been told that deep cycle doesn't like short charges, and reg batteries don't like being drawn way down. Perhaps an "educated expert" can clarify?
Never seen a 6V battery around here for under a hundred bucks.
There have been reports here on the barn that the optimas don't last like they did years ago.
As for a lead acid battery,
Ask for a Group 1 battery for 6 volts.
9 1/8 length, 7 1/8 width, 9 3/8 height
6v group 1 batteries are found by the following numbers;
NAPA - BAT 7244
Exide - 7200
Tractor supply - Com 1 HP (part number 0470506) I think.
Autozone - 1-6 volt
Ultrapower #901MF from Deka
interstate part # 1-VHD