It can be a good investment but the return will have to come from principal reduction and appreciation, not cash flow.If you can continue to find and flip with this type of profit, I'd recommend making hay while the sun shines and continue to do it (at least until this opportunity dries up).  

Essentially keep your powder dry because you're going to need it.  

I'm not pulling up all the OSB and rafters, just replacing the shingles and underlayment and replacing any rotting areas.

Looking to diversify since cash flow is drying up here.

His current 9 to 5 is doing yacht maintenance but is skilled in many other home repair fields such as demo work, dry wall, painting, carpentry and finishing work.

-Check the dish drying rack/dishwasher.

I purcahesd a duplex last fall and we noticed the neighbor has a large amount of dirt leaning up against the back of our garage which is starting to rot the wood of the garage. 

Let it dry, then paint the floor with Kilz and install new carpet and padding.

We are dry here.

TSP is a powder you add to water so if you wipe down drywall with it make sure the sponge is damp and not soaked then make sure everything is dry before you paint.