Look at the lumber yard for sound insulation. 

If waiting 5 days to formally ratify a contract means you get your keys a week and a half sooner (and you the flipper have unloaded the property a week and a half sooner)...

we may hit a price plateau short term. but long term we still have room to grow just look at Vancouver in the north and SF in the south. we are not even half of their price, more like one third. if you are cash flowing, then hold them for long-term. you can always refi to get some equity out. if you are struggling with cashflow, then now might be a good time to unload.

Things like going to a lumber yard and getting specific 5 ply 1/2" plywood, no matter the application.

Per Lumber Liquidators, Utility Oak Grade Flooring is:"Utility grade flooring Will have defects, knots, open knots, missing tongues, machine burns, splits in the wood and short pieces (12"-8").Sold as is-no warranty, no returns, no cancellations.This product comes in square-edge or v-groove and may be mixed product.

You drive to the job site, load it into your truck and then drive it to your storage building and unload it.

I'll probably unload it next year if they don't renew.

But if you are still looking for the materials to build your own you can find most of those materials at any local lumber yard and the faces you would have to special order to spec.

The cost of this "improvement" is an important, decision-making piece of data (because if I can't unload this cost onto the tenants, the deal won't work). 

Exit strategies, how fast and how well I can unload a property.