[Kirby64]

The sensors are very cheap:

https://www.arducam.com/arducam-ov5647-standard-raspberry-pi...

If you want a fancy one with a lens and an IR cut filter it'll run you a grand total of $35:

https://www.arducam.com/arducam-ov5647-noir-camera-board-w-m...

Sure, the extra stuff like LTE modem, battery, solar panels, casing, etc, costs a whole lot more money, but these things clearly are built cheap. The optics and imaging sensor is a joke compared to real, proper cameras.