Mesh renderer for multi-parts model

Hello,

i created multi-part(20 - 30 parts) animated model in 3ds max. for example:

my file name is "Build". other models(windows, doors, walls...) under build file.
i m adding to my unity project and wanting mesh renderer /on off.
but i inspector tab not contain mesh render for on / off for "Build". if i add mesh render , it is not working.
Mesh render is only working separate parts.can i use mesh render "build" file for all parts?
is there a solution way for this issue?

Thanks

 

can you give an idea for this about ?