Winter battery maintenance

I'd probably pull it inside and put it on a timer. Should I do a 1-Amp or more?

I pull all of my batteries out of the vehicle and put the batteries inside if the vehicle (or cabin as the case may be) they're in won't be used in the winter.

Admittedly, I've got a hangar to put them in but I much prefer to swing by and check the status, plug in the trickle charger, switch what's charging, inside a warm building than doing the same checks or activities out in the cold.

At a minimum, suggest a good charge and a complete disconnect (i.e. unclamp the leads, etc).

Regardless of battery chemistry, I believe it should be physically disconnected. Most (all?) batteries can be stored below freezing. Lead acid and AGM can be charged below freezing.Lithium batteries should not be charged if they are below freezing !

IMHO, batteries should not be left on a maintainer continuously. Hook your maintainer to a mechanical lamp timer and charger for about 4 hrs per day.

You can do it either way, totally your choice. But you need to make sure you've disconnected the battery so you're not draining it due to parasitic draws. Many, if not most, factory battery disconnects don't completely disconnect the batter from things like radios, lights, and various other devices. A couple of weeks, or less, will give you a dead battery.

I spent $30 on a 10 watt solar maintainer since I don't have electric where I store the trailer, and didn't want to pull the battery. I've checked it a couple times and it seems to be doing the job.

A charged battery will not freeze until the temp hits -80F or so. I leave mine on a maintainer and check it now and then. I have not had any issues.