At one point I even tried working with the tenant to see if a different due date would help based on when he was getting paid, but he said he was fine and his new job would help him get ahead.

Looking ahead to my next project, do you have any advice or resources for finding off market deals? 

If you are close to retirement or looking to plan ahead I would recommend, Cashing in Tax Free written by Leslie Pappas. 

In my view you are a good 6 months ahead of the guy if you buy now. 

How much further ahead will you be financially with this approach vs a 1-unit property?

I wish I had thought of house-hacking at 21, nice work getting ahead of your peers! 

Don't look now but the 10 Year US Treasury is dropping like a rock over the past week currently hovering below 4.1% ahead of the FED Rate decision. 

It helps handle all the "back of the envelope" calculations a head of time for all listings within 50 miles of your city.

. - Any Acquisition Manager I was assigned to had something that came up on multiple occasions where they would either start later than agreed upon or not show up at all without a heads up.

From this post, I would say you are in the weeds.You both have great starts with paid-off houses and limited debt so focus on the next step, not ten steps ahead.