Post it on fb marketplace and boost the ad and I am sure you will get a million messages but don't make your ad sound like a motivated seller.

Meetup.com is a good resource for those but some of the groups will also post here on Bigger Pockets Marketplace too.

I had a call this morning from a Homicide detective as suspected murder was holed up in one of our houses..

If I am selling a car and just put it in my yard with a sign, it might sell.I will have a much better chance if I also advertise it on FB marketplace AND Craigslist in addition to putting it my yard.

You have to play detective and keep asking around.Although this is a Real Estate deal and will make great money. 

While to some extent software can act appropriately based on averages, that'd different than actually understanding the marketplace and workflows and optimizing.  

Local REI groups and Facebook marketplace can also be great sources.

We've installed the Moen leak detection device, which detects leaks both hot water and cold water, and monitors water usage and gives you weekly reports.

In the end it comes down to being able to detect the BS and find the right people once you do that you are in pretty good shape.

@Bryon Andrews was spot on in his advice too - do some Zillow and FB Marketplace surfing every few weeks to see what rents in the blocks near your property have been renting for recently, and track how those fluctuate over time for a few months.