A 12 stamp based system. 

Rules:

• Limited free seats per workshop.
• One free seat per workshop and one 50% off per workshop, not the 2 in the same workshop. 
• Stamps never expire, but when the stamps are full as in 12, they have up to 2 years to redeem them 
• The user have to be registered as a user ID
•  Unique to per user ID, the full stamps can be gifted or transferred to someone else.
• Workshops specifically made for clients are not included in the stamps. 
• Workshops that are free are not included in the stamps system.