Vaccination and health: not required.

Consular visa required.

Validity of the visa: a single entry. 

Term to stamp the visa in the passport: Three (3) months once authorized.

Term to enter Costa Rica: Once the visa is stamped in the passport, it must be used within a maximum of sixty (60) days.

Maximum stay of up to thirty (30) calendar days extendable up to ninety (90) calendar days.

Documentation to present:

1. Valid passport or travel document. Only machine-readable passports or travel documents will be accepted, in accordance with the guidelines established by the International Civil Aviation Organization (ICAO), and with the validity determined by these guidelines.

2. Visa, when required as established in these guidelines.

3. Proof of economic solvency, with a minimum of USD$100.00 (one hundred US dollars) per month or fraction of a month of legal stay in the country.

4. Ticket, ticket or return ticket to the country of origin or continuation of the trip, or the navigation plan showing the port of destination.

5. Not to have impediment of entrance to the national territory.

Requirements:

1. A visa application letter addressed to the Costa Rican Consul containing the following information: full name and surname, nationality, passport number, address, purpose of your trip, the duration of your trip, the place and date of arrival and departure, profession or occupation, exact address in your country or in Costa Rica, place and date of birth, fax number or e-mail for notifications, the date of application and signature.

2. Passport which must have a minimum validity of 6 months and photocopy of the entire passport.

3. Tentative itinerary or temporary reservation of your ticket. It is recommended not to purchase the airline ticket until the visa is approved.

4. Proof of economic soundness (bank statements, salary letter, statements, etc.) for the last three months.

5. Provide a criminal record for the last six months.

6. Passport size color photograph (2x2 inches).

7. Proof of legal status in the United States as a permanent resident (green card, work authorization card, student visa, work visa, parole). Individuals who do not meet these requirements must apply for a visa in their home country.

8. The Consul may request additional documents if necessary.

9. Those foreigners who enjoy an asylum or refugee status in the United States, must present additional documentation such as birth certificate and letter from employer duly translated into Spanish language and must be consularized or apostilled.

10. Application form. This is an official document, so only application forms issued by the Costa Rican Consulates or on this website are accepted.                                                            

More details,here.

Note:

1. Once all requirements are submitted the Consul has 30 calendar days to resolve the visa application. 

2. Once all the requirements are completed, the Consul will inform the interested person of the date and time when he/she will be informed of the resolution. 

3. If the Consul has any doubts about the documents presented, he/she may request clarification and may also request a personal interview with the interested person. 

4. The visa must be used within sixty days, from the respective notification to the applicant or his representative,and is valid to enter the country only once.

5. Each consulate individually establishes its schedules and procedures, according to the personnel it has, so you should inquire with the Costa Rican consular authorities on these issues. 

Email: EMBCR-DO@RREE.GO.CR

More information here or en la Dirección General de Migración y Extranjería de Costa Rica.