Hi Kristal,
Do you have a low-voltage contractor that you work with for other items like running cable/internet, access control, intercom, etc.? If so they will have preferred camera products that they like to use, and it's great to have the contractor's assistance specifying, installing, and servicing the product. Of course you'll sacrifice some degree of affordability if you go with this option.
Another option is to use a consumer grade product like Swann
www.swann.com/us/swdvk-855808wl. Their systems can typically be installed by on-site maintenance staff, and I've found them to be almost as reliable as professional grade systems over the years.