I think you'd need to offer a pick-up service for this to work, but it sounds like a great idea to me. Maybe start with posters on bulletin boards in grocery stores; the kind with a tear-off telephone number. A short ad in your local newspaper would be great if it's not too expensive; that would reach a lot of people who live near you (to keep pick-up area small).
Where you may run into difficulty is selling machines. Many people are so busy working jobs they are not interested in sewing anymore.