People actually monitor the New Member Intro forum so they can welcome new members. 

I have reoccurring income month in and month out.

Will be closely monitoring this thread.

With doing that, you have a reoccurring fee of $2-300 per year.  

I use Mint for day-to-day spending tracking, making it easy to tag and categorize expenses, mostly for monitoring active checking accounts (my wife and I each have our own checking account, as well as a joint one).

Butterfleye, blink, nest, and canary all have great cameras that can recognize faces, only record when something happens, and are around $100-$200 with a $5-10 subscription for cloud usage.If there's activity you'll be able to monitor it and even see what's going on in real time.

I currently have 5 units and its been a pain using excel to manage the expenses that I incurred from purchasing the units to the monthly expenses or even monitoring the incomes for each of the properties. 

I went with no (I paid $99 for him to clear the pipe) and haven't had any issues since (I think the clog came when some other guys did some work prior using high pressure water to unclog the washing machine drain pipe as well as the first floor kitchen sink drain which they said was full of years of sludge but I digress).If this is a reoccurring issue I would find a roto-rooter guy who can get video of where the clog is coming from and have him document the location of the clog to show which unit the clog is coming from.

I have cameras to monitor the units and only allow 2 guests max upstairs.

Best way is to go and visit, other than that monitor the MLS closely and you'll see patterns emerge.