that material is stored in unheated warehouses all the time, you can store it in the garage. as @Brad Lighthall mentioned just let it acclimate for a couple of days in the house before installing it.

Copper out last all other materials for mains, if it is a main go with copper not pex I've replaced so many pex water mains. 10 years is a short life span, the foundation could of settled and caused the brake

When buying sizeable or large quantities, I'm curious what your strategy is for negotiating discounts with your material vendors and distributors. 

We intend to remove this covered area because it promotes junk storage.

•Charged me $500+ in "materials" and refused to provide me with receipts and just gave me a generalized itemization and charged me for debris removal when I had done it MYSELF.   

They want a house with four walls, a functioning roof, and rough and finish materials that work.

There will be promoters at various tables some of whom will be hard money lenders, get their cards and the flyers with their info.Be prepared to partner on deals until you have a proven track record of 5 deals or so, then the hard money folks will talk to you.

And folks who maintain jobs and are apartment material will of course keep paying rents (albeit with some concessions, perhaps). 

If they had already prepurchased some of the material needed for the repairs and things like smoke detectors, would they normally be able to use it on a different home or would they get upset over it?

I don't know how to price the materials.