If its ugly, or maybe a barking dog next door, or even on a slightly busier road.  

Taking everything into account and some numbers are estimated high it figures to make $125 per door after we pay property management. 

Through active marketing (door-knocking, advertising, yellow letter campaigns, etc.), reaching out to these owners can yield leads that in turn can lead to property purchases as a significant discount from market value.The process of finding discounted properties, especially for the newer investor (like me) can be daunting.

Christophe,You need to first start with how much money you have to invest in the United States.If you have large quantities of money 500k, 1million etc. then more doors open up for you. 

There aren't many updates that need to be done to make it tenant ready; a couple door replacements, small bathroom fixes, and cleaning out tell unfinished basement which the owner started to make into other apartment but ran out of money.

My next door neighbor also has a a duplex and he's looking to sell and I want to buy it.

Good point @Ben Leybovich  I'm not a big shot investor, don't own hundreds of units (yet) and after 7 years of investing, getting a realtor license and dealing with tenants; I just now feel I know enough to take the next step and get a small multi-family (under 75 doors)Call me conservative, cautious, scared or insane but reading posts in this (wonderful) community of young, inexperienced wanna investors aiming at apartment buildings as first investments with 16K total cash reserves or questions like "how to start with no money at all?"

Stumbled across this on a local municipality's site - gave some good info on door locks that I was unclear on with regard to Texas Property Code.https://www.youtube.com/watch?

Gist of the idea is you develop your marketing advertisement (think: car magnet), hire a driver who is already actively driving around (Lyft, Uber, etc), and have someone (or many someones) marketing your company while they drive. 

Can I remove carpeting, doors, toilets, sinks, place a dumpster in driveway, blocking garage usage?