I am going to buy 2 other used vehicles cash and then the only other revolving debt on my credit report will be my primary residence loan.

Our intention is to purchase a 2-4 unit home and live in one of the units, thus taking advantage of FHA/203K financing.I cam across a HomePath duplex property that looks very promising.  

As you acquire more debt, in this case real estate being good debt, versus credit card debt (revolving), which is bad debt, you just need to be open and honest in the interviews and there won't be any issues. 

Beside the two ideas you mentioned (hard and private money) you might consider a bank, something like a business revolving line of credit might work depending on how fast you work.

It's a revolving door,, If you choose to do this rent by the room, you will need to put a room number on each private room so if you ever have to file a eviction the room is designated,, I would suggest the electronic key pad type lock for main entry and one for each private room so easy to change codes.

My main questions revolve around financing.

In my old highschool, our personal finance class revolved around a curriculum from Dave Ramsey, who bad mouthed mortgages and everything.

The next question revolves around financing for future rental properties.  

We currently are saving that monthly income in an account separate from our personal accounts but I'd like to know the process if for some reason we ever need to use it month to month.The next question revolves around financing for future rental properties.

I like the trail cams as well.