The cost of a Defender camera depends on which model you choose. The 4K Sentinel is priced at $69. However, you’ll also need to purchase a DVR or NVR for an additional $249. The 2K Guard costs just $39, or you can upgrade to the 2K Guard Pro for $126. Finally, the Phoenix 2M sells for $131. Defender cameras are some of the most affordable cameras on the market.