Depending on the specific location, this should be possible with relative ease, and relative low cost. Rebuilding a washing machine to accept bitcoin, can be done for under $50. The one factor where you have to look at, is what does internet cost. you can hook all washing machine to basically a single mobile connection, but preferably you're gonna want a hard line. Dependable on where you are... these might be expensive, but overall they are pretty cheap (you should be able to get one for a low as $10 a month)

One factor to also keep in mind, is that you gotta adjust with exchange rates, with the way prices going now... it won't be fun to all of a sudden having to pay 20 bucks for laundry...