We have sold a few of these out of our shop.. Some people wanted them so we have always carried one or two for those nitches. They usually are constructed well. But smell the back before washing. If it smells like bad latex then prequalifty with your customer. Otherwise, wash the crap out.
If you wash it expect the deep colors to bleed. That magenta and denim I see in the pic are suspect and the leather will stiffen. If there are no bleeding issues we'll wash these, but we have a flatbed washer so the rug isn't wet for very long.
It can be cleaned with a wand on a tack-out floor, you'll just leave a lot of water behind. Each tuft is hand sewn and aggresive agitation will tear some loose. Many of the ones I've seen have a soft back with no latex and can be immersion dry cleaned.
PS: I say send it back to the guy that sold it and tell them to clean it.
We've washed a few rag rugs, check for color fastness and thread strength.
We get all kinds, home made, professional, had one made with her fathers ties (we drycleaned), we also had one that the mother had made of jean material from the time the daughter was a child to adult hood. (HWE hand tool).
They seem to be getting more popular, many we HWE flat, flip and do the other side as we do braided rugs.
If we sold it, I'll be glad to clean it!!! hmmm maybe I should go through the show room and tell dad to get rid of the seagrass rugs.. :? Oh wells someone always wants them even if we tell them its a throw away if you spill any "real" soil on it.