I mounted a Roam 4' awning off the back of my TrailRax Half-Rack. For sitting on the beach with the car backed up to the Surf-line. Kept the profile low. Seems to work well.
Roam Vagabond Roof Top Tents are on SALE - 20% off!
https://www.northridge4x4.com/roam-vagabond-tents
***Disclaimer*** Yes, that's a Jeep in the picture.....But don't let that stop you, these are nice tents!