How To Calibrate A Long-Range Quadcopter Commercial Drone

If you plan to use a long-range quadcopter commercial drone either for personal or business purposes, the best way to learn is to try operating one. But, before you start getting your hands on it,

How far can drones fly? How long will they last? Are they too expensive for an average person to own? Are they safe? And are they worth the cost? These are the common questions people ask when