you can also monitor the free mls sites and contact the listing agent as soon as something drops.  

It'll be interesting to monitor.  

Does anyone use any remote monitoring systems that are really affordable (like a couple bucks/month) that use a cell network and not need a internet connection for tracking temperature of smaller apartment buildings?  

I recommend that you consider looking into using software to assist your management. 

I currently work a traditional 9-5 for a chemical company (I have a computer science/software background.), and work part time for a realtor/real estate investor.

I use an online company to manage billing and tenant correspondence and it works all right, there are many companies and software solutions out there to help with that.

But, there's a BP member that created some software for doing that (I haven't used it) you might want to check it out.

I am an upstate NY software engineer looking for a way out of selling my time.

I get MLS listings set up by an agent but I was using RedFin to run the comps, RedFin changed their software and they don't offer the comp tool anymore, I don't like what they have now.

I've worked in it for many years so software glitches bug me.