You could always join AirDNA for market data...  

House hacking is an incredible way to get into buy and hold investing with a relatively low financial barrier to entry. 

So is data crunching - as an urban planner, I love using those skills in conjunction with Census data (and I'm oddly thrilled about the new Census this year) to track trends in demographics and real estate values over time to spot areas that are likely to see short and / or long term growth in both cash flow and equity. 

With the market this hot I can afford to wait for a better/bigger entry point but I also see the merit of starting my practical learning now.

I use a spreadsheet to enter simple data in to use as a comparison and calculate the comps.  

Even though I could show that the autopay was set up and the account was well funded, they would not remove the entry on my score (which is totally in their hands).

I am wondering what are some resources, preferably free, to get market data for the area I work in?

As I start looking at new cities and regions, I am curious to know what resources, data points and indicators others are looking at to help inform their next investment area. 

What are some data points that can help build businesses credit, such as: having a Dunn & Bradstreet number, age of business, having a cashflow on the books, and having a physical phone line with a 411 listing.What ways can this help with flipping houses?

Don't start moving the goalposts (i.e. by inflating the sell price or lowering the reno budget without data to support it; using 80% instead of 65-70% in the equation above to sacrifice your eventual return) in an effort to wedge a square peg through a round hole.Not every property you analyze works, and providing them with a "low" offer isn't taking advantage of them.