Either buy a power washer that the soap dispenser attaches to, Or use a coin operated self service car wash.
For soapless washing, I had a small, fixed (non-adjustable) brass nozzle that put out a very forceful but small stream of water from a garden hose. I might have purchased it at Harbor Freight, but that was years ago.
I saw that one and it does connect to a garden hose, you just need the right adapter. We use the same quick disconnect sort of nozzles and wands at work. One part just screws onto your faucet or the end of your garden hose. Harbor Fake as some would call it has a similar model.
Agree, if what you are talking about is what I am seeing, they are just quick connectors like for compressed air. I Have them on all my hoses, sprinklers and nozzles to connect to the garden hoses. I got mine at the farm store. Not all interconnect like air hoses.
For heavens sake. Talk about making a problem where there is none. Just get the other half of the quick disconnect screw it onto your hose and be gone with you. Are you really that bored you have to come here for this? If you can’t figure this out, how do you remember to slow down before sharp curves.
I have an MTM PF22 foam cannon that I use with my pressure washer. Works very well, produces a nice thick foam. I also have the Chemical Guys foam gun (same thing as several others sold under different brands) for the garden hose. Both of these items have the job of putting soap/foam on the car, neither is made to blast dirt off the paint. That’s the job of the pressure washer (without the foam cannon attached) or the hose with a normal spray attachment.
That cheap thing you linked to from Wal-Mart isn’t going to do much for you. It’s $7 for a reason. I would suggest simply going to a pay-n-spray DIY car wash bay if you don’t want to do a proper hand wash.