Just make sure you find someone who has similar lifestyle as you (noise/cleanliness/etc) - vet them just like you would a normal tenant and interview to get a sense of their personality.3) I purchased in 2015 so prices were lower than now (from a cashflow perspective), so may be harder to attain now, but the other 2 units + 2 parking spaces paid for all the expenses w/approx $400 left over... but I also sacrificed area to get a good deal/income I wanted. 

The crew was nice and the staff was nice but nothing like our everyday grind.

It was good to me but constant grind.

It is a slower grind but can be a little safer.

Nobody goes to Costa Rica to hear the noise of planes.5.

Within a month, I am getting calls at all hours of the night with complaints about noise, smoking, screaming, and the like.

Mailbox money is always better than doing the grind to make your money .   

From my research it seems that homes built after 1980 or so are supposed to adhere to stricter guidelines for fumes, fireproofing, noise-proofing, etc. when separating small multifamily units.

You've only owned for one year so it's unlikely you've dealt with many applications, noise complaints, un-mowed lawns, pet violations, non-paying tenants, evictions, unauthorized tenants, hoarding, evictions, and other problems faced by Landlords.

Instead of consuming information/data by the masses, I guess I am trying to figure out how best to filter out the noise.