The program will double LINK purchases up to $25 per card holder, per market day. For each dollar spent with a LINK card at a participating farmers market, individuals will receive a $1 coupon. So, if someone buys $25 of food with their Link card, they will get $25 more for free. Link Up Illinois Double Value Coupons can only be spent on fruit and vegetables. Coupons are not redeemable for cash or change.