The payment amount for each unit (i.e. Adult, Child, etc.) is listed in the booking details. The discount amount is also shown for any promo codes or credits used to book, and Klook will refund the discounted amounts per unit.  Be aware that any promo codes used can’t be returned to your account (unless the promo code is from a Value Pack with a policy that allows the return of promo codes). For add-ons or other upgrades, you'll need to check its separate refund policy.