From what I heard/learned about gas power washers was to get one with a Honda engine and a CAT pump. Such as this one:
https://www.pressurewashersdirect.com/Simpson-ALH3228-S-Pressure-Washer/p16096.html
... and look at the attachments tab. The water broom works pretty good on decks, patios, driveways, etc.
I don't think the electric power washers would have the 'power'. Plus, electricity and water don't mix very well.