This eliminates double bookings and allows the cleaners to be aware of last minute bookings without a source constantly monitoring and updating. 

It's called the "Cycle Monitor".

The environmental controls are very tight and underground storage tank (UST) operators are held to strict standards for regular inspections and monitoring. 

Talked to a local investor today and he suggests staying closer to home so I can monitor rehab.  

Choose where you can very clearly describe what you expect, move by move even  the most detailed and above all else (even if you hired the controller): a way you can monitor what very specifically is getting done.   

Fall & Spring HVAC Service Target Date: April and October This service can aid in early detection of costly problems and save the cost of expensive, emergency service.A/C Service Includes: Check condenser coil, adjust operating pressures, monitor safety controls and starter capabilities, clean or replace filter, adjust blower components, calibrate thermostat, measure for proper temperature differences, clean condensate drain, tighten electrical connections, measure voltage and amperage on motors, lubricate moving parts.

I can't really complain about the 10% when the most "work" I'm doing is monitoring things from my phone.

I tend to acquire multifamily property in markets with a compelling growth story (of course the future is uncertain but it pays to begin in the right direction), improve the property to bump the income in the front side of the investment, then monitor for the optimal exit point.  

Monitor the results and tweak your message if needed. 

Do you charge for monitoring and maintaining vacant units?