Welcome to the site.  

There is opportunity cost in it but it won't negative cash flow as my mortgage amount and payment is small vs prevailing rent, with a big margin.

We added on site laundry and redid all the landscaping.Doing all this allowed us to increase rents 30%+, which means the three rented units cover the PITI for the property so we have no housing costs.

I wouldnt waste time on these sites.

Great that you joined the site!

A very good place to start would be the large amount of Podcasts available to you on this site.

Everyone is familiar with Craigslist so there is no need for further discussion.Zillow Rental Manager allows you to post from a single portal and it posts to multiple sites: Trulia, Zillow, and Hot Pads (maybe others). 

Its such a blessing to have a site where like minded individuals can come together and throw around ideas and help each other scale their business to the next level.

I am on this site to network a bit.  

I'm a newbie too, so I can't answer them ... but, I will say also check out "Meet Ups" through this site and through the "MeetUp" app.