When "Allow guest login" is set to "Yes" guests can view their bookings from the guest login area. The template variable [GUESTLOGIN] will add a link to the guest login page to your confirmation message or to Auto Action Emails.
Cancellations
You can allow guests to cancel bookings themselves. By default the system uses the policy you can set under SETTINGS -> PROPERTIES -> BOOKING RULES. You have the option to override these settings for offers or individual bookings. If you allow cancellations you can send your guests a link to let them cancel via the system without contacting you. Include the template variable [CANCELURL] into your e-mail confirmation message. This will add a link to the guest login where the guest can cancel the booking.
When guests cancel a booking they will receive a system notification that the booking was cancelled. If required you can set up an additional Auto Action Email in SETTINGS -> GUEST MANAGEMENT -> AUTO ACTIONS.