Also, check to see if your jurisdiction is practicing "Just Cause Eviction", which went into effect statewide earlier this year for municipalities that which to opt in. 

I walk every house prior to check in to ensure a five star review. 

As someone who has read Harry Potter, it seems the best way to get the attention of the landlord is to send a scary looking giant to their home residence with a kindly worded letter.More seriously, I was on the other side of the coin previously where my wife put the ads up under her accounts instead of mine, so I couldn't check them without getting on her phone and I was inundated with people looking to see the property (probably 50 over a 5 day period) and was trying to send semi-personalized notes to each one--and it all ended up being too much to handle and I ended up ghosting or not replying to many people after I found an applicant. 

Here are a few suggestions on how you can maximize the wealth of information available: Check out the blogs and podcasts, or take advantage of the search feature (magnifying glass).

Last I checked my average across 30 units was something like $179/door.

I just want to sit back and collect cash flow checks. 

Check out this BP article about how they come into play with the BRRRR method.

I would say the data is representative of the Dolores neighborhood as well.

Sometimes maybe often times they aren't doing enough to track down the owner or owner's heirs and just collecting checks from the court.

I'm checking out Jamil Damji's Astro Flipping coaching program.