CakePHP penny auction script per seat

Looking for a plugin built for my existing php penny auction script, written using cakephp. In Seat Auction, admin defines a limited number of seats and limited number of bids in admin panel. Auction runs for a specific number of hours (also pre-defined in admin panel) when all seats are sold. Every user who wishes to participate in Seat Auction must buy a seat before he could participate in that auction. When user buys a seat, they get a pre-defined number of bids for that auction and they are not charged for placing those bids on specified auction. However, they cannot use these credits in any other auction and there is no value for unsued credits. If users received limit bids and they run out of credits, they cannot buy more credits or buy another seat.