I use this system for temporary security camera setups at field locations to monitor equipment. With it we have caught 2 incidents of theft, prevented 7 incidents of unknown intent (They spotted the camera and then left), captured 4 incidents of vandalism (3 of which we caught), and captured 1 incident of a couple "exercising" under one of our trailers.
http://www.samsclub.com/sams/4ch-dvr-4-camera-sds-p3042n-us/prod12720074.ip?navAction=push
We use this system on continuous recording which gives us about a week of footage (Motion mode we found to be unreliable when we need the footage). The cameras can see anything within about 100 feet. They can clearly see IR (In the dark) within 30 feet and clearly see faces within 15 feet. It is wired which protects it from jamming and interference.
I would advise placing the DVR in a secure location (We use a trailer or a office normally) and then running the wires with tack hooks to the camera locations. Hiding the wires is not necessary as long as it is flush with the surface that you are running it along. Most people don't touch the wires except in the area near the camera. I would also advise placing the cameras watching "critical areas" (Like your oil tank) and also place them on routes of egress (Access points to protected area like doors and gates). It is best for the cameras to have some overlap so you know which camera to switch to when you are reviewing footage.
I would advise you check the area you are watching frequently so you know what part of the footage to go over. Reviewing 1 hour of footage takes 5 mins if the area is "quiet" (Basement) and 30 mins if "active" (Public Place).
I hope this is of help.