In my younger days, in the park.
Hobby days, did it in one of those prefab storage buildings in the parking lot of Home Depot. It was a two-story thing, with windows. I think folks outside heard us...
On the beach in Jamaica...
The dressing rooms/booths at Pro Bass shop would be ideal. Bench to sit on in there, a full mirror, door that closes and locks, and open at the top, but nobody can see in up there. I've been meaning to try that out...
Anything in a parking lot works. But as playIV alluded, kinda hot right now. I have wondered if any ladies here are game for a "car date"...I have full tinted windows and a sun shade.
I'd love an under the table blowjob at a restaurant someday...
...and bj or fs in a movie theater...