Based on your business model, you set a weekly budget that will never be exceeded. While the number of leads you receive daily may change, you will not be allowed to spend more than the amount of your weekly budget. Unlike other paid Google services, you are only charged for the leads that you receive. Several factors determine what a specific lead may cost, including service type, local competition and the type of lead. Each viable lead received will count towards your weekly budget and if you feel that a lead you receive is not valid, you will have options to dispute it.