We will make money through subscription. You first 300 vouchers are free to use for as long as you want. After 300, we will ask for a small monthly fee (less than $10) to manage more vouchers. The monthly fee will help keep our business running. I think, with 300 new customers already, you will feel the benefits outweigh the cost. The subscription tier will also include enhance features such as user analytics to figure out who are your customers.