Workflow between Revit and Unreal

Hi all,

My office uses Revit for 3d modeling and now that Unreal is free we believe we can create a workflow in order to provide beautiful walkthroughs. My biggest question is has it been done, and if so how? Everytime I search for this topic I never get a definite answer on how to do this. My biggest issue now is every time I import a revit file (i export to max and then export as a .obj) if i were to adjust the textures the whole house is that texture, so would I have to import layer by layer or is there an easier way?