The more you buy, the cheaper it becomes! A package of four cameras is 40 USD/Eur, or 10 USD/Eur per camera. Buying 8 cameras takes the individual price down to 8.65 USD/Eur. 12 cameras is 8.33 USD/Eur per camera. And 20 units is a mere 7.50 Eur/USD per camera. Shazam!