We're wondering about various what-if's though, such as what if the people tear up the place, what if we don't want to rent to someone in particular due to references or credit or pets, etc.

Because if I use my credit card to pay for a pizza, I pay a $0.00 fee. 

All complimented with Amazon fulfillment centers, google, and more tech manufacturing jobs.The bad reputation of “Detroit” comes from OOS investors wanting sub $40,000, D class properties in poor condition, because they pencil out to 2-3% deals on paper.

I don't accept credit card payments for this very reason.

If your rate is low on the 5 unit, I might consider the possibility of a line of credit for my equity instead of an entire new mortgage.  

I have taken all my taxes and insurance out of escrow, and I run them through credit cards to rack up points, so I pay a lot of bills every year.3.

I called Home Depot, they told me to dispute the credit card charges so I did.  

One of the things you can start doing is reviewing your credit score and work on improving it if needed.

We have some credit card debt we are hyper focused on paying down , and 34K in my student loans (not touching currently due to SAVE plan with the zero percent interest).

Most of my clients run their SFRs at a 25%-30% (excluding vacancy/credit loss) operating expense margin and most of the banks I deal with on their DSCR loans underwrite using 35%.