I would use the bedroom because of the extra heat you will get from the lights. The use of 3 sets of dual 4' T12s plus 3 sets of 2x overdriven T12s increases my bill +/- $30/mo. That's just an estimate compared to older bills and not hard figures of actual wattage used.
IMO caladiums do better with a winter rest and tuberous begonias may be the same way but I'm sure they will also do well overwintered indoors. I've done both with caladiums and the ones that get a rest seem to be more vigorous. All of my coleus is 2 years old and was overwintered indoors as was my impatiens which had 3 flushes of blooms over the winter and got a little messy but after planting them out in spring it was well worth it. I also overwinter some new alocasia and colocasia divisions from my larger tubers along with many aloe vera and a tomato and pepper or 2 of the more expensive, harder to find or favorite varieties and may get a dozen fruit from each over the winter. It's more something for me to do over the winter than anything though with a bonus of fruit and fresh air and of course some great plants to put out come spring.