Salary and remunerations

Article I, section 1(7) provides, " the President shall, at states times, receive for his Services, a Compensation, which shall neither be increased nor diminished during the period for which he shall have been elected, and he shall not receive within that period any other Emolument from the United States, or any of them."

So, the U.S. Constitution made it possible for a poor person to become President by providing a salary for the office. The President's salary cannot be raised or lowered during the period for which he shall have been elected and he shall not receive within that period any other Emolument from the United States, or any of them.