Breely allows you to create and use gift certificates.
Enable Gift Certificates under Features & Integrations
Gift certificates can be created in the "Gift Certificate" section.
They can be used as a payment method, for example, to make test purchases.
Gift certificates are redeemable for a dollar amount.
When you enable the Gift Certificates feature a new form will be created that can allow clients to purchase a gift certificate. You can also add the "Gift Certificate" question to allow purchasing on any form and customize the amounts shown.
You can also import gift certificates from a spreadsheet and preserve any gift codes from another booking or payments system. This can be done in Gift Certificates by selecting Import from the "..." menu.