Battery question for cart little used

[engine95]

I wasn't quite sure how to word the title, but here is my question.

I've done a lot of reading/research and I understand ah ratings and most things batteries. I'm leaning towards going with 12 volt AGM batteries for cost and their ability to hold a charge longer. (less drain compared to FLA)
The cost of AGM and Lithium make it difficult to justify their use in 6v and 8V configurations. Especially because it sits so much.

I'm rebuilding an 85 club car with a SS conversion kit from cartsunlimited. It's 36 volts now until spring when I will make it 48 volt.
The cart will spend most of it's time on a new Summit II charger as it only gets used when at our property. Maybe 3-4 times per month when we are there. It spends all winter at our property that can become inaccessible for a few months. Making it difficult to make sure the charger is on, and water in the batteries.
When it does get used, it's very short trips with maybe 2 miles total for the day.

With what I've read, FLA shouldn't be trickle charged. So even leaving the Summit II on it all winter may take the water down below the plates before I can check them. And, often we will have power outages that may reset or disable the charger, thus leaving a discharged battery come spring.
These situations lead me to believe that I would be trashing 6v 8v batteries within a couple years.

With this situation, am I justified going with 3-4 12 volt AGM and trying to get a 65ah and higher? Seems even 35ah will work in my situation.

I know this is not the normal situation for most folks here, but I was hoping to pick some of your brains for more info's.
Thank you