@Lilith M HaasI would have your plumber camera the line too and see if there is anything that can cause issues, it only cost me $200 bucks to check my lines to make sure there were no issues, we had serious issues with ours and replaced the lines and added clean outs, had them recheck after a year for piece of mind and was all good, no issues for 2 years now but we have in our lease no lady products or wet wipes down the toilet, and if there was a clog and these items were found that the tenants would be responsible for the bill.

You could also get a mobile hotspot connected to your cell plan and place it at the house (for wifi for cameras)

Sounds like it is time for cameras and the police..............all the best!

I asked him about the surveillance camera he said he doesn't want it anymore, the camera is still wired and I'm concerned that he may be still monitoring my activity on the driveway since the camera can be connected to his phone.

Also have cameras in especially for night time, with signs so he knowsI’m not very swift when it comes to installing cameras

Radon detector pretty pricey, infa-red camera, are you able to check electrical circuits? 

Also added camera systems to keep an eye on things.

I have a triplex in Los Angeles and I need your suggestions for a good but not too expensive hard wired cameras that captures images and sound to monitor some suspicious activity.

Simply Safe systems are great to use so long as you keep the electricity on.Otherwise, if you have boots-on-the-grounds, PM, Realtor, etc. that can pop by regularly to check locks and show that the property is being checked on.You can install live, or dummy cameras, on the exterior of the property as a deterrent as well.Best of luck to you!!

I had plumbing backed up and had the camera and they have already clean out.