Business visas last sixty days, and can also be obtained at a travel agency if you present a written invitation from a Russian firm or partner, three personal photographs, and a photocopy of the first six pages of your passport. These visas are issued based on applications submitted by the Russian companies, joint ventures, etc., to OVIR departments. Foreign companies stationed in Russia should appeal to the Consular Department of the Russian Ministry of Foreign Affairs. The application should include all explanations regarding the requirement for the repeated entry visa. The travel agency will then forward the info and the application to Russian Embassy.
Visitor visas require a personal invitation and an accommodation guarantee.
Before passing through customs you have to fill in the customs declaration and indicate the available amount of foreign currency in cash and traveler's checks. The customs declaration should be kept up to the end of your stay in Russia, as it may be required for departure formalities. However, the amount of some items brought into Russia is limited by the local customs regulations. These are, for example, alcoholic beverages, etc. The customs requirements are subject to frequent changes, but any Russian Consulate, when issuing your entry visa, should always provide you with the information about the latest charges, if any.