Ficus love the sun, although they are advertised as indoor bonsai. If you can manage the watering, I would place it on direct sun light. Also, the soil that all this mall-sai vendors use is straight bark-peat moss that waterlogs easily, the first thing I have done to the few ficus I bought from stores is remove the soil entirely. You can repot ficus in summer, just keep it under indirect sunlight for a couple of weeks. I will be repotting mine next week.
As Donovan mentioned, the main thing with them (as any tropical tree) is to keep them away from cold temperatures. Anything below 40 can damage the tree.