Buses for Puerto Viejo (10 kilometer from Congo Bongo EcoVillage Manzanillo) and Congo Bongo EcoVillage Manzanillo leave from the Terminal de Buses de San Carlos in San Jose.
The bus company that drives there is called Transportes Mepe and their ticket office is at the end of the terminal.
There are two towns called Puerto Viejo that you can catch a bus to from this terminal.
You want Puerto Viejo de Talamanca (also known as Puerto Viejo de Limon).
The cost is around $12.00 and it will take about 5 hours (ask the driver after Puerto Viejo to stop by Congo Bongo EcoVillage Manzanillo) and the bus makes only 20 minutes stop in Puerto Limon for you to use the bathrooms and get something to eat or drink.
When you reach Puerto Viejo you have to take a taxi to Congo Bongo EcoVillage Manzanillo the cost is about $14.00
On the website of Transportes Mepe http://www.mepecr.com/ you can find the schedule.