Puntarenas is NOT a destination for travelers, it is a hangout for tourists and commercial interests reveling in closeness to Puerto Caldera (cruise ship terminal) and relative closeness of San José. The beaches are dark volcanic sand, the water is murky and there is rubbish aplenty, not to mention suspect sewerage and runoff handling.
Monteverde is a nice nearby destination (but distances can be deceiving - the road is a slow climb on anything from unimproved to swampy and can take 1 - 3 hours, depending on conditions.) It is a mountain rain forest preserve - yes, it is likely to rain, mud and fog while you are there, which is why you can visit rain forest and see many interesting denizens not to be found elsewhere. The park can also be very crowded.
I agree with iahphx
- CR has changed for the worse, IMO overused, abused and riven with highly inflated prices, often charged by overextended providers of services that use a plethora of excuses for mediocre and even lousy service.
Today, much of Costa Rica is not Green, it's "Greenwashed" - prefixes like "eco-" and the like on every other word, excuses to charge extremely high prices for only modest products because of the "eco-" use, high density and overuse in too many places, unsustainable and nature-unfriendly practices (gensets in the mist) and environmental abuse.
To add to this dismal picture (with a few possible exceptions,) petty crime is alive and well throughout the country. Once confined to the Caribbean coast and centered in Puerto Limón and nearby beaches, now one must watch their belongings in hotels, airports... basically, everywhere.
There are some decent destinations, but be sure to check the weather - CR can be nasty in the "green" season (what they now call the rainy season,) and that season varies according to where in CR you are - Arenal is dismal in December, when the central plateau or Pacific coast are quite pleasant, for example. Central coastal areas can be humid and wet, with many biting insects: in the wet, er, sorry, "green" season can be infested with "purujas" - no-see-ums that can fly in squadrons through normal netting and may leave inflamed itchy welts that will persists for weeks.
(Also avoid the Manchineel / Manzanilla trees lining beaches near Manuel Antonio - they are nasty pieces of work whose sap can cause severe damage to human skin, which is why the worst slaveholders in the Caribbean would tie "miscreant" slaves to these trees to punish them. Ask a guide or park guard - be aware of these.)
Check the weather trends here: link
If you are interested in putting something together and are not so familiar with the country, consider using old Costa Rica hands like Costa Rica Expeditions
Do your research thoroughly
- and don't rely on old information. Hotels / resorts that were splendid some years ago may have been "mined" by management and now moldy and old.