What are the visa & residency requirements in Cameroon?

"In order to visit Cameroon, foreign nationals 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 proof of sufficient funds to cover the duration of the stay. Depending on the purpose of the visit, additional documents may be required. In order to obtain residency in Cameroon, foreign nationals must submit an application to the Ministry of Territorial Administration and Decentralization. The application must include a valid passport, two passport-sized photographs, proof of sufficient funds to cover the duration of the stay, and a letter of motivation. Depending on the purpose of the stay, additional documents may be required. Once the application is approved, the applicant will be issued a residence permit," said another expat in Cameroon.