Save money with BC Ferries Experience card

it's a stored-value card;
if you purchase ticket with this card, you save $12.25/Vehicle and 3.45/person 12 years or older.
as far as I know there is no expiry date, it's cash card.
you need to load minimum amount for being eligible to the discount:
Passenger only, new minimum of $65 - to receive access to Passenger-Only reduced fares on participating routes; and/or
Vehicle and Passenger, new minimum of $115 to receive access to Vehicle and Passenger reduced fares on participating routes.
a little secret: from Greater Vancouver to Sunshine Coast, you only need to pay one way ticket, you do not need to pay your way back to Greater Vancouver no matter how long you stay in Sunshine Coast. http://www.bcferries.com/experience_and_coast_card/what_it_is/