The embassy Immigrant visa unit posts the Fee for an immigrant visa (CR-1, IR-1) that is $380
They tend to not cover the K-Visas that are non-immigrant visas, the fee for them IS $100, or the equivalent in the local currency. This is the fee paid for processing the DS-156 (Non-Immigrant Visa application)
The K-3 pays the same fees at the K-1 so look on the Fiancee visa page for fees.
QUOTE
Payment. Please pay the application fee ($100 dollars for each applicant) ON THE DAY OF THE INTERVIEW only after an Embassy employee instructs you to do so. We accept dollars and rubles. Credit cards are not acceptable.
http://moscow.usembassy.gov/consular/consu...cord_id=fiancee