Use Batsons Creek Slipway in the town:
Batson Creek Salcombe[slipway] - Boatlaunch
Easy slip, lots of car/trailer parking.
I was down there at the beginning of June for a week, the guys running the slip/boatpark were very helpful.
Can't remember the costs but I know it didn't make me wince!
You can get daily harbour dues.
Lots of info from the locals in this thread: