When I discuss the potential usage of drones with (mining and road) construction firms, I got specific requirements. In terms of surveying, they sample the altitude of route of the road in every 15 (or less) meters using rtk gps - centimeter level precision. Thus their main requirement for a drone service is to obtain the exact altitude of the sampling points (every 10-15 meters along the road). Is it achievable using rtk gps + lidar sensors? And secondly, how most of the drone companies survive when they only focuses on just getting 2d-3d maps and post processing them without giving (exact)coordinate of the maps and altitude for surveying? Could someone with corresponding experience explain this?