I believe the bright blue stretchy thing that ctb posted is the same "beach tent" my friends have.
Which would be this, if I'm correct: https://www.rei.com/product/123573/neso-1-sunshade
Kind of cool, as it can be used not just to cover your doors / for an awning like they're using it, but anywhere. However, my friends use it as intended (with the sandbags, not as an awning) and it doesn't play well with wind. Maybe holds in place better when it's strung up to a van?