Many fine kayaking trips can be planned using wheels to walk on to the BC Ferries. This way you can avoid making reservations and paying fares for your car. If you have someone drop you off at your departure point, you can save on the parking fees too. You can launch from one spot and catch the ferry back from somewhere else. Just make sure you have a ferry schedule along!
Summary of some Ferry launching situations:
Horseshoe Bay - convenient pay parking at the ferry terminal. Drop your kayak and gear at the passenger drop-off, park your car and then load up your kayak. Buy your ticket then wheel across the road through the gate and left down to the ferries. Have your boarding pass ready.
Tsawwassen - convenient pay parking at the ferry terminal. Drop your kayak and gear at the passenger drop-off, park your car and then load up your kayak. There is a door to the right of the ticket agent that you can wheel your boat through. Have your boarding pass ready. Upon return, wheel to the right of the admin building and enter the passenger drop-off area through a convenient gate.
Departure Bay (Nanaimo) - Easy launch from boat ramp very close to the ferry. Wheel out of the terminal, keep to the left and turn left at the traffic lights, then right down to the ramp.
Swartz Bay - There is a small beach by the government wharf just east of the ferry. After leaving the ferry, wheel over to the left and look for a way out of the terminal. Sometimes you can go through the staff parking. Or use a special gate to the east of the admin building. Wheel out to the road, turn left, pass the truck terminal and take the next left. Total distance is about 1/2 km, so you will want a pretty good set of wheels.
Duke Point - no launching possibilities within reasonable walking distance.
Galiano Island (Sturdies Bay) - Easy launch from the beach, or the dock.
Mayne Island (Village Bay) - Easy launch from the beach next to the bottom of the parking lot. Note that the gate is locked when there are no ferries running, including several hours during the day.
Pender Island (Otter Bay) - Not the best - Launching is possible from the marina to the southeast of the ferry. This would be about a 3/4km walk up & over a hill. Not sure if the marina would charge a launch fee.
Saturna Island - Launch from the dock next to the ferry.
Saltspring Island (Long Harbour) - In the bay to the southwest of Long Harbour, there is a rough beach and a steep-ish trail down to it from the road. If paddling in to the ferry here, remember to paddle in the bay to the southwest of Long Harbour itself.
Langdale (Sunshine Coast) - This is a frustrating situation. There is a fine beach next to the ferry, but the gate is always locked. A few years ago the ferry staff opened the gate for a large group of paddlers - you could always ask. The other alternative is to wheel out of the ferry parking lot, turn left and take the first left back down to the beach through a kids camp. Usually the camp doesn't mind, but if they do, continue south down Marine Drive to Hopkins Rd. Distance to the camp is about .8km, to Hopkins about 1.2km.
General Notes;
Launching from a beach usually means carrying your kayak down to the beach, sometimes over logs. You will need to empty your boat to carry it down, and then repack it.
Launching from a dock often means carrying your boat down the ramp, which can be steep depending on the tide height. Lifting a loaded boat into the water is asking for boat damage and physical injury, so plan on loading/unloading at least some of your gear while the boat is in the water next to the dock.