"Have you ruled out multipath issues?
Signal multipath:   Errors can be introduced when signals are reflected of buildings of geographical entities such as large rocks, etc. As the less direct path will be longer and take extra time, this can add…"

"Could a forum representative comment on any updates related to this question? I am interested in using UAV's for inspecting homes. If I have permission from the home owner/bank to inspect a property do I still need to acquire a commercial license?"