Razor wire is a commercial product that is considerably more expensive than regular barbed wire, and comes in rolls that are probably best handled with a forklift. It’s nasty stuff and would probably not be worth the space it would take to store, or the special equipment needed to handle it.
Regular barbed wire is plenty useful for regular perimeter security in my view, and it is plenty economical to stock a couple of rolls away. One great use for it is “tanglefoot” around any area that is out of sight, or just on the other side of a fence or gate. A quarter mile roll is a lot, especially in an urban setting, and if a few of your neighbors can all stock a couple of rolls, you will be ahead of the game when it comes to securing a perimeter...
Razor wire is available here.
http://www.fencing-online.com/razor_wire_3_ctg.htm
I ordered mine 3 weeks ago. If you order 10 rolls shipping is free.