Custom Start Point Landing & Starts

Hi, i have a question and i hope someone can help me. I started to fly what i call River Runs. Flying along the river as close as possible to the ground. Now i noticed some rivers (Mekong as an example) could be a problem because there is literally no airport for hundreds of miles. Thought first i could use my Husky Float for it but my problem is if i land and want to finish for the day i can‘t start from the same position on the ground. Is there a way how i can change the start from custom points and save the spot where i did land so that the game would start from the exact same spot where i did close the game? I know i could just start from the air but i noticed yesterday that i have severe control issues when i do that. Its also a pain in the … finding the exact same spot somewhere in the middle of nowhere from scratch every single day.