Thanks to all who made great suggestions. After a fair bit of kerfuffle, trips to hardware stores, tracking down lost tools, forgetting why I went to the basement etc. I now have my trailer in the storage facility, smelling quite nicely of peppermint, Bounce sheets, and some mouse repellant sachets. I got my son to lift out the batteries for me, and those will go in the garage attached to the Noco charger. Along the way I found out that the power jack will not work when the battery is disconnected, even when hooked to the tow vehicle, and the manual mechanism requires more torque than my drill can produce. Also got a perfect strap to haul out those batteries kindly given to me for free by a golf cart store. Now to start planning some trips for the spring!