Enter the Opportunity Knocks Sweepstakes with AARP for the chance to win the $50,000 grand prize! They are also giving away $20 Visa gift cards each day! enter by logging in with AARP and filling out the entry form. If you don't have an AARP account, it's free and easy to create one. Users must be 45 years old or older to enter and unfortunately, residents of Florida are not eligible. You can enter once per day and may receive up to 30 additional entries per day for completing the trivia game. Sweepstakes ends October 31st.