X-Cart Pro(open source ecommerce code) Modification needed!

X-Cart Pro is an open source multi-vendor ecommerce shopping cart system. (go to [login to view URL] to see x-cart pro) It is written in PHP, Smarty Template Engine, and MySQL. I need someone to modify or add some additional features I need. Please see the following: I’m debating on 2 options as follows. Please let me know which would be cheaper option and give me the quote on both. Option 1 1. Upon transaction, payments gets deposited to the seller’s paypal account directly, minus “seller’s fee.” 2. Seller’s Fee adjustable through site admin. 3. Listing time adjustable through site admin. 4. Listing fee adjustable through site admin. Feedback rating system 1. Buyers and sellers are able to leave feedback upon transaction. 2. Option of “positive”, “neutral”, “negative” on the feedback and percentage of positive shows up next the each account holder’s screen name. feedback comments show up on feedback page. 3. List feedback score, percentage, 4. Automatic reminder email to buyers and sellers to leave feedbacks. Option2 1. All transaction happens through site as it is set up, but the distribution of funds happens automatically(each month or week?) to each account holder instead of how it is currently set up to do manually. 2. Seller’s fee adjustable through site admin. 3. Listing time adjustable through site admin. 4. Listing fee adjustable through site admin. Feedback rating system 1. Buyers and sellers are able to leave feedback upon transaction. 2. 1 to 5 stars to choose and the total percentage shows up next to each account holder’s screen name and feedback comments show up on feedback page. 3. Automatic reminder email to buyers and sellers to leave feedbacks.