At that point she'll be eligible for a 1031 exchange.

I've had a fairly easy time wrapping my head around all the fundamentals of REI, and many of the concepts are so simple I can't believe they never occurred to me all these years when I was losing money every month with my rental. 

Am I eligible for a Solo 401k, or is an SDIRA my only option?

The housing market is fundamentally strong—there is demand for housing, many areas have varying degrees of shortage of it, employment is still relatively strong (although there are now some cracks appearing in the foundation), and wages are growing.  

Most small-to-medium sized businesses are eligible.

Hey Sela,Your professor is correct in terms of the fundamentals of real estate, buy low and sell high.

I no longer am eligible for the FHA loan as a result, and used all my capital for my home.

Both markets have a good combination of strong economic/demographic fundamentals and cash flow whereas some of the others, although they cash flow well, have stagnant of declining populations and jobs.

The perfect scenario is you get a property under contract and share it with your lender, who will then rerun what programs you're eligible for with your new 700 credit score. 

@John Morganas @Jaysen Medhurst pointed out you have many things going on here.If your LLC is a single-member LLC, you may be eligible to report the income earned by the LLC on your personal tax return.