Here's a site I found that will give you an idea on prices.
http://www.cctvcamerapros.com/...5.htm
Just a word about brands, Sanyo and Honeywell are cheap garbage, their picture quality is crap, and their overall build quality is cheap plastic crap.
Speco Technologies, Pelco, GE Electronics, and JVC are excellent, pretty m uch the top of the line.
As far as any other brands go, I've never dealt with them personally so I can't vouch for them.
When looking for DVR's the number of channels = the number of camera's it will handle (ie 4 channel = 4 camera's) The most channels you can get is 16, you can install more but then you are looking at more DVR's and a MUX (Multi-Plexor, it acts like switcher so you can acces multiple DVR's with one monitor). You can use any standard LCD monitor as your monitor.
If you want a camera that you can move you will need to look at PTZ's and then you start getting into high dollar camera's (from $900 entry level domes to $5-10K military grade PTZ's that have windshield wipers for the lens') plus you'll need to get the controller and they are just as expensive.
Also let me add that a building the size of your standard fast food joint will require roughly 1-2K ft of siamese for 16 camera's. so budget roughly $1500-2000 for wire, connectors, and any hardware (anchors,screws, toggle bolts ect) that you will need.
So 6K for a handful of IR camera's should be enough.
Keep in mind that if you hire an electrician (or anyone qualified for that matter) to pull your wire for you will take a large chunk of your budget (up to 1/2) for labor alone.
But don't do it yourself if you don't feel confident in doing any of it yourself.