The 3 inch netpots should work very well for those rooms.

Are most of the roots in the bottle ? And main roots hanging through the neck ?

If that's the case then I would take a good pair of heavy shears and cut the bottle away. Be careful and you won't do hardly any damage. If the roots become too restricted then the plant will Bonsai. I have seen roots clog a 1/4 inch drip line 6 inches up and then stop growing. Took me a few to figure it out.