I like propstream.com mosty for deep and wide (best i;ve found) data/lists and deep dive into individual addresses. 

Does anyone know of an individual or company that would co sign with a stranger (me)?

While the interest rate might be higher, you eliminate the risk of needing to refinance or sell later, making it a safer option if your goal is to hold the property long-term without any financial uncertainty.If maximizing cash flow now is a priority and you're comfortable managing the future refinancing risk, owner financing with a balloon could be the better choice.

The state the property is located in, homeowners' insurance policy, and whether you rented as an LLC or individual all make a difference.

How about the individual who took a social media guru course and now believes there are sellers lining up willing to accept terms seasoned real estate investors have never seen in their lifetime. 

There are so many choices out there that you need to make, and you have to look at what you really trying to do with it, which is asset protection for your personal assets most likely.

You can do everything from strategizing your incomes together or individually and loans jointly or loans borrowed jointly to maximize the 10 total financed properties.

If a cash out refinance, many lenders will allow the cash out to satisfy the reserves requirement.DSCR lenders generally let you vest either individually or as an LLC.

For appreciation, the Columbus market is a strong choice.

Given the choice between cash now of say $500k, or REAL equity of $600k, I choose $600k equity as long as the $600k is greater on a RISK ADJUSTED BASIS.