If I decide to build a greenhouse, I'd like to try bananas as I plan to keep it warm enough at least for citrus.

Questions:

1 - what are good, edible banana varieties that are on the smaller side, and can grow in a greenhouse that is maybe 12' at the peak, considering the pot itself has some height to it?

2 - what size container is needed?

3 - do bananas have trouble ripening in winter light levels in the mid-atlantic?

4 - what's a good online nursery source for plants?

5 - temperatures - in winter, where should I maintain temps, and, if I keep the rootball warmer with heating cables, does that allow me to shave a few degrees off the air temp?