If the lease is signed by the owner of the property, locks, and security cameras belong to the owner and we (the management company ) just facilitate self-showings and then help the owner manage those showings and manage those tenants once the unit is rented.   1.

I just installed outdoor cameras.

I opted to buy a used camera and did it myself, it will pay off in a few homes, the value here is I can walk away from a home before even paying for inspection if there are a lot of hidden issues, or negotiate the price down (with photographic evidence).As an example, my most recent purchase, 1968 brick home had some cooling issues and I suspected attic and insulation, and what happened was they added blow-in insulation and covered suffit vents up. 

Replacing a fuse box with a breaker box (has to be licensed by the city), running a sewer snake through a cleanout hole (I don't want anyones feces on my body, not even my own), crawling under a house to fix plumbing (I'm claustrophobic and have panic attacks), dealing with intruders you catch on security cameras (I call the police and meet them there). 

This would include site prep, fence, basic electric, cameras and a simple office along with the buildings. 

Apart from getting a camera and inspecting the drains there’s no way to tell.

Use Realty.com live camera to look around the neighborhoods Google Earth photos may be a year or two old.

I don't think you'll be missing something with either choice. 99% of what I end up doing is with pretty basic stuff: e-mail, browser, maps, flashlight app (amazingly handy), camera, weather apps, calendar, productivity (pages, numbers, and keynote, the iOS equivalents to word, excel and powerpoint), calculator, kindle app, iBooks (mostly to capture .pdf documents), banking apps (from your bank), open table (restaurant reservations), trip advisor app (handy for finding stuff near you, though the map apps are pretty good at this, too), airline apps (flight status, online checkin), clock (haven't used a watch in years, also for timers, stopwatch, and alarm functions), pandora, fandango, flash seats (concert tickets), and a few others.These phones are really handy when traveling.

We also have either Ring or Nest doorbell cameras or outdoor security cameras.

Install a Nest thermostat and cameras on outside if poss.