Also, older buildings may have lead-based paint, so you should at a minimum give her the EPA booklet "Protect Your Family From Lead In Your Home" and sign a disclosure document about what you know or don't know about lead in the home.5.

If you do so the income from that asset now becomes taxable income, whereas any income generated by the asset inside of Roth 401k can be pulled out as distribution tax-free. 

Do you try to pay based on what you think the value the property is generating, prior to potentially gaining the upside?

So many of the variables in your analysis would be people and their opinions on value and where the market is going.As you mention, after tax cost is a concern as your rentals may be generating taxable income however your rent is not tax deductible. 

I'm here to learn how to leverage that to generate more wealth and income for our family.

The sale generated the recognition of gain. 

Get LOTS of leads, make lots of offers close a few deals.

We have a property in Memphis that is generating $7,000 dollars a year in net cash-flow (property is 100k).We want to buy another 3 properties free and clear BEFORE we refinance them, to group them together and LLC them.However, we want to know IF we can get a HELOC loan first from this property (or others in the future) BEFORE asking to refinance them?

It would likely lead to more work in finding some new tenants as well.  

His rent would only be the cost of PITI, so this would not be generating income, yet it would provide additional write offs.