There are 5 main ways to travel in Costa Rica:
1. Bus
2. Taxi
3. Uber
4. Walk
5. Car (Possible to rent)
For long trips to the Pacific Coast or Caribbean I advise taking a bus. Our bus prices have been $4,500 (Manuel Antonio), $2,450 (La Fortuna), and $2,750 (Monte Verde) for the trips. You can also take the public bus to close by towns like Heredia or down town. The bus price for down town is $265 and $600 for Heredia. (All prices in Colones (mil))
Most people take a taxi around town or to the mall. However, I suggest taking uber instead because it is cheaper and the drivers have to use WAZE which is an app I would suggest you download before coming to Costa Rica. Also download Uber with a card that is able to work out of the country. You may use a taxi but make sure that Maria is on. Maria is the meter that keeps the distance and price in check. Some taxi drivers will give you a flat rate and usually it is more than the actual rate.
Uber is frowned upon here by the locals because the Taxi drivers have been on strike from uber because people are flooding to use uber. Uber not only uses a gps and is cheaper but you can easily split the fee with another person and you can also get candy and usually a person who speaks some English. This is great for people coming that do not speak Spanish fluently.
For school, I often walk about three blocks. I have walked from the mall and have walked to downtown and it is possible but if you are not good with directions I would not recommend walking to a new place. There are some areas of town that you need to avoid and walking and getting lost is not the best situation. If you are wanting to live a healthier lifestyle while here than I definitely recommend walking every time you have the chance. The distances are fairly long but not difficult. Do take an umbrella or rain jacket with you if you decide to walk anywhere because the rain is unpredictable.
If you are having a long weekend and feel comfortable driving a stick shift I would recommend using a car rented instead of taking the bus. You can make it there with an hour or two to spare because of the various stops the bus makes on its way to the location. Having a car is also convenient if you are staying in a hostel away from town or other activities. The buses have broken down and they do not have A/C. A car can be very handy but also a lot of responsibility. They are around $5 dollars a day.
You should travel when you have the chance and weigh the pros and cons and prices of how you will reach your destination. I have used all of the above methods other than renting a car. However, a friend here has rented a car for ten days to travel the country with her boyfriend and she is nervous. She is from Denmark where they grow up knowing how to drive a stick shift so I highly advise if you are not comfortable driving a stick shift that you hold off on renting a car for safety.
If you have any questions about traveling with transportation in Costa Rica feel free to email me or comment below and I would be more than happier to help!