For growth investors, cashflow should be treated as a defensive metric.

Seller financing and self How did you add value to the deal?

tons of real estate investing podcast on apple podcast such as BiggerPockets, Lifetime Cashflow through Real Estate, Multifamily investing made simple, just to name of few. don't forget to listen to motivational and self improvement podcasts because mindset is everything 

Usually the radiators are deal-breakers for me but I would be honest with yourself and ask your self who your tenant is. 

Upon move out and receiving a portion of the security deposit, we were charged an over $400 cleaning fee in addition to some normal wear and tear items because they exceeded the apartments self calculated normal wear and tear allowance.

I would use them myself but I self manage my own properties..

All the more reason to hire a good property manager, or if one insists on self-management, make sure you get to the property at least once a year.

Townhome/condo/SFR - rent by the roomADU / multifamily units - self explanatory Storage / Space rental - Rent extra space/bedrooms/garage for storage, driveway for car parking, etc.

Your best offense is a good defense.

In fact, there're several "layers" of restrictions, including "at-risk" rules, basis rules for pass-through entities, hobby rules, new (as of 2021) "excess business loss" rules, special rules for Section 179 and business interest, self-rental rules, vacation homes rules, and more.