What's the best way to get between Managua and Monteverde. I am trying to keep it as cheap as possible without having to switch buses 10 times between. Is there a simple way to do it? Am I better off just booking through a large international bus company?
Rome2rio says bus via Puntarenas, for a total cost between 24-35
EUR. The international bus company is Transnica. The second segment is a local bus N. 675. For completeness sake note that Transnica has some not-so-positive feedback on tripadvisor dating 2013. I don't know if the situation has changed since then, but it might be worth asking around in Nicaragua.
There's another, more expensive option with 4 different buses, but why would you want to do that to yourself.
Note that Rome2rio prices might not be up-to-date and must therefore be double checked on site.
An even cheaper option could be hitchiking, of course.