Even if they are in a redemption period, they are earning interest in the even the owner redeems it and if they don't, they can foreclose and get the deed, so not sure why they would want to unload it but to answer your question, yes.

I purchased cabinets from IKEA, made my own vanities from prime lumber and fabricated concrete counter tops for the kitchen and both baths.

Starting to unload.

Or do I start with a lumber company for quotes? 

The provider has unloaded all that risk to you as oppossed to a turnkey purchase, where you don't own it until the work is done, the inspections are complete, there is an appraisal confirming the actual value, and likely there is a tenant in place.What could go wrong with the BRRR - a whole lot more.  

In your case, however, the seller is Freddie Mac and the appraisal report must be fed into that big database thing by your lender prior to closing, meaning that in theory the right hand of Freddie Mac could glance over at the left hand of Freddie Mac and see that they are unloading an asset for well below market value.... in this case, the seller could (if they simply wished to double click to open a file) see this appraisal report prior to closing, and kill your deal.I have never seen that actually happen. 

I don't know what you could sell the lumber/timber for?  

Have you checked out Lumber Liquidators. 

Try Hidler Hardwoods or Hines Lumber.

But I've looked into condos selling dirt cheap, where the HOA fell asleep at the wheel, and owners had trouble unloading their units.