But, what I learned was how to dry out a basement, repair a sprinkler system and winterize it, and what kind of effort it takes to do all of that.

Dry, solid structure, and good ceiling height has made me really look into it.

The non invasive scan is only going to tell us that there is an anomaly there (which we already know) but not tell us why there is an anomaly and what really is there (septic, oil or dry well).

Unlike stoves and fridges, a washing or drying machine can be easily abused and require more maintenance.

If you are looking to buy and hold and seek positive cash flow in decent to good neighborhoods, the market is drying up.

Another question I have is we are finding deals but we do not know if we should place an offer then try and secure lending or should we have some type of DU stamp or pre approval prior to making an offer to avoid being left high and dry with out lending?

We will when the word of mouth market dries up.

I called Serv Pro and they did the remediation work and put drying equipment in place.I don't know what to do next.  

You could start by doing less but the UV light will tell you the story.The problem is that if the pee is near the walls it will be wicked up the wood and dry wall even if they did not pee directly on the walls.Dogs particularly like to lift a leg and pee on door frames and walls.

Any rotted wood that needs to be replaced?