They might refuse since you are not the owner.

Can anyone recommend sources for contact information for property owners?

The answer is yes, but it is generally found when the owner is also living in at least one unit (aka "House Hacking").

Transcribing transactions from bank statements, posting transactions to the correct accounts, and then manually creating an income statement, statement of owner's equity and a balance sheet is a fairly time consuming process and I have not been able to keep up with the book keeping between my regular work responsibilities.What accounting software do people recommend? 

The owner is friend of mine, really good dude.

Additionally, I would like to attempt to do the process Owner/Builder with subcontracting work out as well as doing some of the work I'm comfortable with (I have some experience with bathroom & kitchen remodeling an am not new to the construction industry).

This vary heavily town to town. 20% down is great if buying strictly as investment but if you have a way of owner occupying I would explore that route and apply the 20% down to increasing value of property and instead using low money down loan. 

Can you reach out to their owners and see what they’re doing?

In neighborhood it is very important to present your self to the home owner next to you, this helps a lot to prevent misunderstandings. also this shows your professionalism.

I’ve had most luck with signs in front of my plaza and word of mouth - networking at Chamber of Commerce and chatting with other business owners in the area.