If you want a suction cup, go with this. It will fit pretty much any camera and since it has adapters, you'll have spare parts if anything breaks
its funny how many people don't know how to put up a suction cup correctly. If you wet a suction cup before you put it up it stays. Every so often you pop it off, dab a little water on there and you are good to go. Never had an issue with mine. You can buy a roll of gorilla tape for $6 or $7 or a universal suction cup mount for $10 and not have to worry. I ordered this one can it comes with different connectors so it will fit: https://www.amazon.com/iSportgo-Suction-Different-Recorder-Cameras/dp/B06ZZW2Q77/ref=sr_1_7?ie=UTF8&qid=1504229476&sr=8-7
Cool idea! I recommend trying something like this to get more stable footage out the window https://www.amazon.com/iSportgo-Suction-Different-KDLINKS-Cameras/dp/B06ZZW2Q77