That's Genius when you hit the tennis ball you stop, ive never seen a hanging stop / parking guide before.
I did this for years when the wife could still park in the garage to make sure she had enough room to get around the front of her car to get inside.
Side benefit, it kept her from hitting my mill and lathe.
She made the mistake of offering to let me use the whole garage when I was lusting after more shop space. I don't have to worry about her parking in the garage anymore, so the hanging ball is gone.
The only vehicle I have in the garage is my 2008 Triumph Street Triple. I have a 2007 Element and 2017 Pilot that park near the garage along with my 2019 RAM, if that counts.