Small pressure washer: recommendations please.

When I go to the car wash the seemingly high pressure lance does indeed clean dirt off but it takes for ever .The car wash place doesnt like people using cloths,but after initial wash a good rub over with a cloth removes the stuck on dirt,then repasos again with the washer much more effective but doesn’t use so much water therefore cheaper
 
It would also be very useful if it could take suction direct from a fresh-water river when water usage restrictions are in force, as they often are on the river where I am based.
I don't know if it applies to you 'up the river a bit' but Arzal Capitainerie loan out a pressure washer with a pump to use river water
 
When I go to the car wash the seemingly high pressure lance does indeed clean dirt off but it takes for ever .The car wash place doesnt like people using cloths,but after initial wash a good rub over with a cloth removes the stuck on dirt,then repasos again with the washer much more effective but doesn’t use so much water therefore cheaper
My local car wash has quite an elaborate procedure - spray with detergent solution, pressure rinse, wash with detergent using mop-like cloths, pressure wash again, then dry using cloths and chamois leather, and finally dry cloths to remove the last bit of water and clear any smears from the glass. They have a water recycling system (I thought all commercial car washes were required to have one). I use them because they're good and not silly expensive!
 
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