During the PCB assembly service you might encounter diverse pricing from project to project. The pricing calculated through multiple factors such as: 1. amount of the Pcb assembly components 2. PCB layers, 3. PCBA layers (top and bottom or just a single layer) 4. components cost, 5. tests and certification  In order to ensure low cost and fast production, always ensure design quality and prototyping before mass production. the larger the quantity during the PCB assembly mass production, the lower the price of PCB assembly service will be. Another factor will be if you choose only PCB assembly or one-stop-service . We suggest to let us handle all the components purchasing, assembly and production in order to ensure lower price and higher consistency.