@Thomas Malone As a fairly inexperienced real estate investor, I have not had any dealings with Lee Arnold or his inner circle. 

The limit on scaling is your deal flow (mine never was that good) and time it takes to perform the value add (I got fairly quick for example, my last rehab did all new plumbing, electrical, and flooring.  

Sejin - Have you read your fair share of books as well as listen to podcasts?

The overall LTV (including all 3 mortgages) will be key and your selling point will need to be that the 2nd mortgage ($8k) will burn off in 2.5 years (based on your surprise that it was even out there, I'd recommend that you follow up in 2.5 years and ensure that it's been satisified, so that it doesn't surprise you again in the future).Does the $8k grant vest over the 5 years? 

What do you do to ensure that the tenant is responsible for security deposit disputes since that is the largest reason for owner lawsuitsHow familiar are you with the newly changed laws that can affect you the owner if they are not used correctly?.

Cash flow is helpful because it ensures the property pays for itself and is a safe investment.

Selling the property within your Solo 401(k) and returning the proceeds to the account simplifies compliance and ensures tax-deferred growth (or tax-free in a Roth Solo 401(k.)).

I agree with Aristotle-get paperwork in order now to ensure when the time comes, you have less to deal with.

I am fairly new to real estate, but have been able to get a few properties which will help us own a block in downtown Columbus, OH.

but it also has a couple shortfalls: - Low to fair rents at best - Low rent appreciationI bought fairly smart, but still not smart enough to consider it an immediate good return.