A coworker of mine originated from NYC. They didn't have any space for a washing machine or dryer in their apartment. No one did. According to him, there were several dozen laundry services that they could use, super cheap. All they had to do was put the bag of laundry outside the door in the morning, and next morning would be bag of folded laundry. To me, this sounded like heaven, but it was just common for him.

For less populated areas, this seems like an extension of housecleaning services. I've known a few people that have someone come in, maybe just once a week to clean. Some have laundry done then, others just want the cleaning. Granted, since they would be using your washer/dryer, there is a limit as to how much laundry they can do in a day. Manageable with 1-2 people, but 3 or more, each with their week's worth of laundry could really add up the dryer time.

Talk to your local dry cleaner. They may offer this service. It may be price competitive.