Generally, you want to look into the pressure, water flow rate, physical size, weight, hose length and accessories (nozzle). There's a shampoo nozzle, brush nozzle, floor cleaning nozzle etc.

Here's a rough guide for your reference






Above information is taken from Karcher website. You can check out their website for more info on how to select the best pressure washer for each cleaning purpose.
Anyone else used Apache brand before?

any cheap thick snow foam compatible with apache?