I use Appfolio in our business for LTR and we really enjoy it.

We have a normal REI business with this 4-plex on the side and it takes some juggling. 

Yes you can use the cash out proceeds to payoff a mortgage balance for an investment property since it is still qualified as business purpose use. 

LLC's are more used by larger investors and people who do not qualify under their personal names and have to ue business purpose loans and they require the property be in an LLC and not an individual.

As for cash flow, buy or start a business.

As I've been learning, there are the key taxes to understand when investing into a new area or state:- State business income tax (if you have an LLC)- State personal income tax (if they want to tax you too, even as an out-of-state investor)- City personal or business income taxes- Any registration fees due the city/state- City/state property taxesAnd I'm sure more!

Thoroughly research the industry, field, business you’re interested in to see if there’s a “niche”, unique approach, unserved customer base, or anything similar that can be exploited to earn income 3 standard deviations above the mean.

Then speak with the planner to see what types of businesses / buildings they think are a good fit for the property based on the master plan for the area. 

I've always used my business solely to generate an income/paycheck, however I'm ready to transition and use my experience to facilitate investment opportunities.

So in the mean time, I been keeping busy with working on my own properties and a few small landscape and PM accounts.