. Dedicated to renewing the luxury real estate industry, Sotheby's International Realty offers born-again experiences through a global network of atypical agents.The total investment necessary to begin operation of a Sotheby's International Realty franchise is approximately $40,650 to $285,500 for a conversion real estate office, and $122,150 to $472,800 for a start-up real estate office. This includes $$0 to $25,000 that must be paid to the franchisor or an affiliate as an initial franchise fee. The initial franchise fee for a residential franchise is $25,000 for the first Branch Office, $12,500 for the second Branch Office and $7,500 for each additional Branch Office.