Selling old cameras online can be a great and easy way to clean out your gear and make some extra money, but it is important to sell them in a safe and orderly manner.  First, research the marketplace to establish a fair price for the camera based on its age, condition, and demand.  Once a price has been set, thoroughly clean the cameras, taking clear, quality images, and demonstrating all of the features as accurately as possible.  Find a reputable online forum or platform where the cameras can be safely sold using secure payment options for the buyer.  Make sure to provide detailed product descriptions that include the specifications, prices, overall condition, and any accessories available for the cameras being sold.  Finally, when you're ready to ship the camera, package it adequately for transportation to prevent damage in transit while maintaining your reputation as a seller.  By doing these things, you'll be able to sell the old cameras effectively with minimal risk.