Yep, Blue Beacon, spray only.
Trailer and truck were really dirty after a very dusty Burningman 2022. We came home to a September heat wave, 106 degrees, and I just didn't have the energy, so I sat in the AC and drove out 30 minutes to the interstate where the truck wash is.
They were very thorough, but that means the wait in line can be a bit long. From the time I got there to the time I pulled out was a good hour.
I think it was ~$70 for both. With all the stuff on top of a trailer, you may still have to do a little cleaning yourself. The water and bits of dust and dirt get trapped in and around the ACs, skylights, solar glands and such. It ends up running down and leaving some streaks.
Used a clay bar this year after washing it. It sounds like a pain in the ass to rub an entire 30' trailer with a bar of soap sized piece of clay, but once we got going the 2 of us did all but the end caps in about hour or so. It really cleans up the water spots and other stuff leaving the finish glass smooth.