About 10 years ago I lived quite close to a big fancy automated machine, I tried it a few times, every 6 months they would another option it seemed, HD wash, Super HD wash, Ultra HD wash lol
I saw absolutely no difference moving from the £3 to £8, I only used it a handful of times as it was more handy location wise than it was good,
You can’t beat a bit of hands on elbow grease for cleaning a car to a decent level, jet washing only takes off so much
Now I’m not able to clean my car myself these days
One thing to watch out for with your £5 eatern European or Asian car washes apart from the obvious swirls in your paintwork it will ultimately leave, is the ones that used acid to “clean” your alloys, this ovetime will corrode your brake callipers and wheel hubs, whilst it’s not terminal it can make the affected area look awful especially if you have nice big alloys
If you need to use them and aren’t bothered too much with the paint swirls just ask them what the spray on the wheels and if it’s the acid wash stuff go somewhere else or tell them not to bother with it