The second class bus from the PV main terminal will drop you off along the highway, and it is about a 20-30 minute walk into Sayulita from there. The third class buses that you can catch anywhere will take you right into Sayulita, so that is what I would do.

Depending on how far you want to go, and how fast you want to travel, would dictate whether an intercity or local stop everywhere bus would be best.

We have never had any problems using buses.