I live in Georgia and my basement gets into the low 60s/high 50s on cold nights, but sits mostly in the 60s. The cages are by Tall Grass.
I don’t really have anywhere to keep them on the main level that won’t upset the wife.
There is an unfinished bathroom area in the basement with three walls that I forgot about. The open wall is to the main large space, but I might try using a oil heater in that area and see what it does with temps.
You could create a fourth "wall" by hanging a large blanket across the opening to the main space. Just suspend a sturdy curtain rod from the rafters.