Creative ways to enhance security at a 12 floor office/ retail building
For those of you that own/ manage large properties in the more popular part of town, what are some creative ways you make the building more secure?

I manage a mixed use retail and office building in a very up beat, central part of town. 

We have security but not during all operating hours, we do have a scan card system but it's limited as many of the tenants have clients coming in for appointments and such. Another main issue is homelessness in the parkade which is both for tenant and visitor parking

Looking for new ways to scare off the homelessness and unwanted visitors who damage the property and scare the tenants
[{"id": "gvcprav", "text": "A few ideas:\n\nCameras  \nLights, maybe on motion sensors.  \nSpeakers playing music or some noise", "replies": [{"id": "gve4idp", "text": "I'm not sure how this has worked in larger buildings, but have heard of success for smaller retail centers (playing Barry Manilow or classical music outside in the common areas), 7-Elevens and other establishments.", "replies": [], "depth": 2}], "depth": 1}, {"id": "gvczrop", "text": "Build a moat.!? Lol", "replies": [], "depth": 1}, {"id": "gve49uu", "text": "In DTLA, most buildings have security guards at the property during operating hours. The cost is usually paid for as a pass through on CAM charges (after year 1 of the lease). For buildings that have a scan system, they alert security on the 1st level of any \"visitors\" they have scheduled to come by. If you're not on the list, they call up to the Tenant. It must be approved to gain access to then property. On smaller properties, I have seen the use of a \"day porter\" that has also deterred homeless and tagging.", "replies": [{"id": "gvfibsd", "text": "Smart.", "replies": [], "depth": 2}], "depth": 1}, {"id": "gvfbuh8", "text": "Hire ninjas", "replies": [], "depth": 1}]