B+ motorhomes

Gary, I have a 213. I was interested in adding a second battery before I even knew what coach I was going to buy. I was under the impression that most battery access doors were big enough to remove and replace the battery thru. Not in my case!! Anyway, I think the best way on a 213 to add a second battery would be to refabricate the present holder. Since mine resides under the couch, 2 more bolts to hold a larger, 2 battery tray is a non issue. I also think I would use the same design, but add a plastic tub/tray for the purpose you mention. I figure Target would have some kind of plastic storage box that would fit. I'm sure I will be doing this, but that's down the road a bit. Right now I'm trying to do a neat job with my side turn signals I (and Dario) are adding to the coach body.
Good luck!