Is there a camera hidden somewhere for "Candid Camera"?

And they are not dealing anything and anyway I have no proof of any wrong doing on their side.I installed a 24hrs surveillance system with a camera pointing directly to the entrance of their and 3 other units.

It's a really inexpensive setup and works very well.Or just take photographs with a digital camera or smartphone camera.  

When we got back from vacation we watched the security camera footage and discovered that the kids climbed the fence WITH THEIR PARENTS HELP everyday and used the pool!  

I would just get security cameras set up around the house in etc. 

So while my business is really shut down, these guys have not been as the security cameras show.

Even when you do make a profit, people forget the IRS wants their cut too.Also some people don't realize the flip shows are scripted and the flipper only steps on camera to swing the hammer once or puts up the last tile.

Maybe keep a camera in the vacant units?

Will also be installing internet on this unit so I can monitor my stuff via my IP Cameras and using the basic services of the unit (gas/electric) as I plan to have a refrigerator there. 

We even had one bored tenant install a ring camera to check when the washing machine was done so they could put it in the dryer or check if someone else had finished.