1. Equipment condition: check the overall condition of the second-hand GPS measuring instrument, including appearance, screen, buttons, battery, etc. Ensure that the equipment has no obvious damage or failure.
2. Function test: Test the functions of the equipment as much as possible, including positioning accuracy, navigation function, data recording, etc. Ensure that the basic functions of the equipment work normally.
3. Software and firmware update: confirm whether the software and firmware of the equipment are the latest version. If not, update to the latest version as much as possible to ensure the best performance and function of the equipment when using it.
4. Authentication and authorization: check the authentication and authorization of the equipment. Some GPS measuring instruments need special permission or authorization to use specific functions or functional modules, so as to ensure that you have legal permission.
5. Service and support: Understand the warranty period of the equipment and whether there is reliable after-sales service and support. This is very important for future maintenance. GPS area measuring instrument can provide real-time navigation and positioning information such as longitude, latitude and elevation by using GPS global positioning system. The GPS area measuring instrument uses the positioning function of GPS to get the coordinates of each point, and then calculates the distance, area and other data through mathematical methods.