The exact source of funds documentation will depend on the source. If, for example, the money is derived from salary, the documentation will likely need to include five to seven years’ worth of tax returns. On the other hand, for funds derived from the sale of some asset, the documentation will need to include the deed of ownership and purchase agreement. Because source of funds documentation is essential to successful obtaining an EB-5 Visa, a U.S. immigration attorney should be hired to handle this step in the process.