A general note: Your ability to find a "coupon" or "deal" would probably be affected by the dates of your planned visit.
Very generally speaking, high season runs from about mid-November to the latter part of April, although individual properties determine when they will change their rates.
More upscale properties might be less inclined to offer "deals", especially during high-demand times such as the ArtBasel show, the Miami Boat Show and the Orange Bowl football (American football) game.