Don't really think you should go to two pages. As a customer, I would wonder it the work will be that good, if you need two pages of legalese. We don't worry about unclaimed units. The few that are left around, normally only take a phone call. Use the KISS method as a professional, and if you feel the customer might balk at a high bill make a phone call to protect yourself. Most customers like to know if problems occur and appreciate your being a proffessional. Surprises are what will get you in trouble.