I just found a mini dvr recorder that still has all the same functions as a full size but is cheaper and has a built in memory and records time and date and everything as well.
The price for the dvr is 350 and the colored cameras are 175 each. It all depends on what kind of camera you are wanting, I also have hidden cameras such as teddy bears, sprinkler head, sunglasses, buttons, plants, alarm clocks, smoke detectors.