multiple battery charging station, ideas needed.
If you already have a charger that will charge them full maybe all you need is maintainers......
FWIW, For recharging and maintaining my boat batteries and over winter I've been very happy with my Dual Pro two bank charger. I flip a switch and let them run a full day once or twice a week in winter in a 45° garage. I do use it for lead acids as well.
They are not cheap. A pair of three banks can run 1200 or so these days...