Rehabbing Flooded Houses in Houston (Construction Question)

[Victor Boyd]

I am looking at some flooded properties in Houston.  They are in various states of remediation, from nothing to having virtually been ripped down to the studs.

My question refers to outside frame plywood and vapor barrier.  Is there any good or preferred method to get plywood between the existing frame and the brick exterior walls?  What about vapor barrier (Tyvek or similar)?  

Although I'm not a builder or a construction guy, it seems that when the house is built, the frame is put up, then plywood is nailed to the outside of the frame, then, a vapor barrier is put on outside the frame and plywood, then, outside walls (commonly brick, sometimes something else (stucco for example).

But, once the house is already constructed, the ones I'm looking at that have been stripped inside, it seems difficult to replace the plywood and vapor barrier between the frame and the brick.

Any suggestions?