When a client doesn't pay me, i send them a warning letter letting them know that I will be sending their information to a collecting agency. Usually, within the week, they mail their payment to my P.O. Box. For the customers that really don't want to pay and ignore the letters, I DO send them to a collections agency. They are EXTREMELY easy to use. They may not be the cheapest option, but they work quite well. 5 out of the 6 clients I have sent to the agency have paid and paid quite quick. The website for the agency is http://www.baddebtrecovery.com/ . Thanks and GOOD LUCK WITH THE BIZ!