Payment Groups 

A payment group is a special group type that takes registrations and payments where there are any to take. One tool covers conference bookings, free toddler groups, online giving and monthly subscriptions.

Prices that change on a date, like early-bird tickets, by setting up a choice for each rate and switching its visibility as each deadline passes.
The template-clone-archive pattern for booking many events: a master payment group, safe cloning, linking from the calendar, and archiving past events.
One tool for paid and free event bookings, donations, subscriptions and deposits, with the data collection built in.
Setting up online giving: the donation group type, variable amounts, one-off and recurring gifts, and Gift Aid declarations.
Free events through payment groups: zero-cost choices, the complete-registration button, limits that still apply, and optional voluntary contributions.
Fixed or percentage discounts, criteria based on who's booking and what, and voucher codes applied at checkout.
Failed-payment notifications, reading the Pledges tab, investigating a donor's payment history, and why stale failures cost money.
Giving full or partial refunds, choosing between a refund, a write-off and reducing what's owed, and avoiding chargeback fees.
Letting people amend or cancel their own registrations, editing as an admin, cancelling donations, and clearing leftover pledges.
Booker and delegate confirmation emails, the merge fields to keep intact, and building e-tickets with scannable barcodes.
Payment plans: when money is taken, Gift Aid declarations, recurring monthly or annual payments, and deposit-plus-balance setups.
Options, choices and sub-options with pricing, plus both kinds of limit: how many can book each choice, and age restrictions.
The Data tab: booker and delegate fields, age-dependent questions for children, creating accounts for outside bookers, and custom fields.
Creating a payment group and working through its core settings: registration rules, online and offline payments, and the text people see.