I am new to being a landlord, but have been a tenant my whole life, and many years experience with video. My thoughts about what Ray seemed to be suggesting: Bad. (Although he didn't actually suggest putting up fake video cameras, just asked if you were considering doing so.)
The mere presence of video cameras does reduce incidents, but successfully using the video to prosecute or even just warn an offender will have greater effect. Often a large percentage of problems are caused by a small number of people, so a little goes a long way.
On the other hand, a fake camera will become known to local individuals soon. I knew that one of my former neighbors had a fake camera installed because I overheard him explaining to a police officer why he didn't have any recording of the crime that had just occurred. I promise you, you will never feel so foolish as on the day you realize that you should have had a real video security system.
(BART had a fake camera system and now have to explain why there are no recordings of recent stabbings that took place in their stations.)
A Swann system will run you about $800 to $2k, depending on how many cameras and channels you need, and whether you are willing to buy a year-old model on sale. A cheap investment. They are all color, HD and have night-vision capability. They can be installed by you, your property manager or a handyman. They do require an internet connection if you want to view remotely, and you do!
It is well worth the time to learn how to set up, install and retrieve the video files from them. Do think carefully about placement, because one camera too far away or too high to identify a person might end up being useless.
In short: A real video surveillance system is a great idea!