I have two of these very portable 4 camera systems with small 7" monitors. Works very well when leaving the unit alone for some time as in race weekend where I leave coach in sparsely populated area. They also work well in campgrounds, parking lots or anywhere you wish. I'm not paranoid...I'm just a step ahead of the bad guy. It's like the little "peep hole" we grew up with, but you live in it...not look through it where there may be an ice pick waiting on you. Most times the sight of the camera alone will keep some moving along. It's also interesting to see what your pets actually do while you're away. Someone is always watching everything you do!
https://www.amazon.com/dp/B00ARJQRLU