Coupon Codes

Hi, I currently have Market Press - is it necessary for me to be paying $19 PER MONTH? I was under the impression this was a once off price I was paying.

I'd also like to know about the 'COUPONS' within MarketPress - I do not want to give $ discounts, but instead I want to have some of my VIP customers enter a coupon which will give them a BONUS product - how can I do this?