Here's what I think I require, but you can make suggestions if you like. Am considering going to RentAcoder.com if nobody here can do this. 1.) There are 12 months in a year and during each month we offer "30 units" for sale. 2.) Buyers have option of either Google, Paypal or Clickbank. 3.) Affiliates receive $100 on a $1500 sale if buyer pays 100%. 4.) If buyer pays 1/2 now and 1/2 within 31 days then affiliate earns his part from each payment ($100 total) 5.) Some popup or other calendar appears showing the remaining and available units during the 12 months. 6.) Affiliates may sell as many units as are available, and must be paid accordingly. 7.) Upon paying you are redirected to a download page to obtain whatever additional instructions and gifts. Please request phone number if you desire to discuss, else send your bid and estimated time to completion. Thanks!