What are the visa & residency requirements in Congo?

"In order to visit Congo, travelers must obtain a visa prior to arrival. The process of applying for a visa involves submitting an application form, a valid passport, two passport-sized photographs, and a fee. Depending on the purpose of the visit, additional documents may be required. In order to obtain residency in Congo, applicants must submit an application form, a valid passport, two passport-sized photographs, a fee, and proof of employment or financial resources. Depending on the purpose of the residency, additional documents may be required. Once the application is approved, the applicant will receive a residence permit," remarked another expat in Congo.