Circuits for an 1943 duplex home

[powerplay]

I am competely rewiring an old duplex home with an "fire separation" to the roof, but in the crawlspace, no separation under the common wall. A double garage is detached to the side of the house which I have to refeed power to which is in pipe through slab with old cloth sheathed cable that I am replacing. I am wondering if bringing a separate circuit to feed the garage from the far suite's panel is allowed to pass through the fire separation and across other suites ceiling, or better to staple under the crawlspace? ( I figure I know the answer but had seen cable chewed in the crawlspace)

 

[iwire]

Will the entire structure be owned by one person?

If so you can run the cable anywhere, on the other hand if the units will be sold as condos or whatever you may not be able to run the conductors for one unit through another.