(Don’t forget covid knocked out 6-8 weeks in 2020 so annual 2020 number might be understated).

put some business cards together and go knock on some property management companies doors.

Making calls, writing letters, knocking doors, or anything to help them out would be a great way to see how they're doing it and more than likely you'd learn a lot more quickly than trying to start it all on your own. 

On top of this, you could use a skip tracing service to find phone numbers and make cold calls, as well as knock doors. 

Granted, I could've worked harder, but many times I came home at 8-8:30 PM from knocking on doors.

I'll go knocking door to door if that's what it takes, leave the dirty work for me.

For example, if I knock down the new walls that were put up to separate the units and replace them with doors - would that be more likely to be viewed as a single family?

I know some investors who have gotten a killer deal just door-knocking for seller financing deals. 

I would basically just close on the property, go knock on the door and say hey, I’m the new owner, we’re planning on doing a renovation and re-selling it, how soon can you move out?

If you otherwise have good credit, and your DTI is the only issue, I'd personally if in your situation, go with knocking off the debt, and buying a property, especially if its a duplex or 4 plex and you're going to house hack it, because then you are literally making money off it so its a good deal all around.