Can anyone recommend a decent pressure washer for residential use? [View all]

[July]

My main interest is in something that will work on baked-in "organic soup" (= smelly standing water that eventually drained out of planters after we discovered they didn't have drainage holes in them) on a slate patio floor. I'm hosing it down daily and have scrubbed it on hands and knees, but I've still got brown grout lines and a delicate scent of whatever critter's waste was part of the organic matter in the planter.

I'm taking advice on what brand NOT to buy, as well, if anyone can offer help.

Thank you!