The financed entry into public companies that focus on the construction and rental of buildings (so-called closed real estate funds) has been in the public spotlight in recent years. Many of these fund projects failed. The expected profits did not materialize, and investors attempted to defend themselves against the claims of the banks that had financed their entry into the company. The dissertation first clarifies how the unwinding of related contracts occurs through the bank's assumption of the rights and obligations of the entrepreneur when the consumer has revoked their declaration of intent to conclude the related contract or when the contract is invalid. In the second part, it categorizes the financed entry of the investor into a fund company as a consumer transaction within the regulations concerning the related contract and places this categorization within the context of the doctrine regarding the flawed entry into a company.