I have SwissTrax in my garage in CO and pressure wash it all the time using a floor washing tool on the end of a pressure washer (amazon has them cheap). Cleans up like new each time.
As for cost, I just ordered SwissTrax for my new trailer and it costs about $4/square foot if you want new material. I've found that the company often times has "used" flooring which they have snapped together once/twice at a car show (i.e. Barrett Jackson) that they are willing to sell for cheaper. You are limited on colors as they usually use black, grey, red, white at these shows, but those colors are perfect for most trailers. With that said, I paid $2.98/square foot for my used material (black/grey) and it will be here this week.
I'll shoot some pictures after I install it.
Ryan
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