CCTV pricing is best understood as two connected costs: equipment and installation. Equipment can include cameras, a DVR or NVR, a surveillance hard drive, power supplies, cabling, connectors and network equipment.
Installation cost depends on cable distance, ceiling or wall access, mounting height, trunking, power availability and whether existing infrastructure can be reused. A site with easy cable routes can cost less to install than a similarly sized site with difficult access.
For a reliable budget, define the areas to monitor, camera count, required image detail and recording retention before comparing quotations.