I’ve had nilfisk.
First was a decent motor one, but in the sales. It lasted 3 years before going faulty. It was going to cost a minimum of £70 to get diagnosed and parts are not readily available. Nilfisk said themselves the reality is only the really expensive professional ones are repairable
I replaced it with anothe nilfisk with 5 yr warranty
This 2nd one has a 10m hose length , that makes a massive difference when washing cars as you don’t need to move the unit
I’d buy any brand that has a 5 yr warranty and not send more than your happy to just chuck away as none of the cheaper ones are economical to repair