See earlier post for break down of buildings, with the addition of the 'Chinatown' buildings are mostly by Knights of Dice out of Australia, with the exception of the warehouse that is Micro Arts studio. Also Eastside is all Sarissa buildings.
The only building/ship/crane that does not have a removable roof is the sand coloured warehouse/factory, it is a light weight foam building, all one piece. The living quarters on the ship lift apart, but there is no hold. I may get around to carving one out of the Styrofoam hull, and cut up the deck to create hatches.
The Old Glory resin buildings have lift off roofs, but only a ground floor. One could certainly glue in some supports, and build an upper story floor.
All the wood building (the remainder of the collection) can have the roof and any floors lifted off.