@Darren GregoryYour friend refers to a very old (and long dead) rule, which is why it's best not to ask friends for legal, tax or medical advice :)There are only two ways to control capital gain taxes on selling your own home, and they can be combined.

Looking to work with one lender or two, if necessary, to pull an 80% LTV and then a 90% combined LTV on a second mortgage.

If you'll have a higher credit score after your debt is paid down, HomePossible will likely yield a better combination of rate + monthly mortgage insurance, and the appraisal process will likely be a lot easier to get through as opposed to FHA.  

Do people frequently combine business & personal? 

Hypothetical:                Make 100,000$                                                                Project Growth- 1 Project with Own Profit of 45,000                                  - 1 self funded flip- 2 Projects with own combined profit of 30,000

I suggest a good dose of C combined with B (cause that's inevitable).Just concentrate on #9 and #10 - real estate investing is a long game (at least IMHO).

You can combine county data with a background service like Spokeo, but nothing is guaranteed.

If you combine avoiding closed cities with MSAs that are growing and/or have more tax/business friendly outlooks and invested outside of them you stand a good chance of making some money.

I’ve found a commercial lender that will give me a line of credit on 80% of the combined equity of the properties. 

Or, is the combined loan capped at the maximum loan to value amount?