The Social Security Administration also issues another type of document, a benefit verification letter, which includes more details about your benefit and can serve as proof of your income from ...

One of those documents will be a “proof of funds” (POF) letter. This real estate paperwork ... already had your lender verify your source of income and the amount of money you have on hand.

The guarantor would have to submit a Letter of Guarantee and an Income Certificate before the visa can be obtained. Believe it or not, the United States does require proof of financial solvency ...