The amount of dispenser units and associated DOGIPOT® SMART Litter Pick Bags™ will vary depending on the location and expected dog traffic. Installing enough dispensers in the right locations within in dog-friendly areas is critical to maximize usage and increase pick up rates. The locations should be in places where most dog owners will walk by (e.g., entrance to park area) and at reasonable distances apart so a dispenser is never too far to retrieve a pick up bag. A good starting estimate of the needed litter pick up bags would be at least 1.5 rolls or 3 header paks per month per dispenser. Monitoring usage from there will indicate whether usage is greater and more bags or less bags are needed each month. Never hesitate to contact DOGIPOT® for assistance in determining your product needs.