I'm building an item mediator portal, something like ebay where people can sell stuff and other people buy it. What payment gateway or systems out there to use that does this? What I want to do is have the sellers connect their account to the system to receive money and the buyers just pay with credit card OR from their account. I'm also taking a percentage of the items sold.
How would I go about setting up the logistics and what 3rd party system would I be using?
The best way to do this would be to setup a payment processor to accept credit cards for the items being sold. From there, you would have to program your website to create a balance for the seller which would include the amoutn of the sold item minus the fees your site deducts. The final step would be to deposit a seller's funds to them either through ACH or paypal.
Buyer pays with credit card >>> You
You subtract seller fees
You transfer balance through ACH or Paypal >>> Seller
An example of a company you would use is cdgcommerce.com which will set you up with a merchant account and gateway such as authorize.net
Your coder would have to build all of this into the code to properly deduct your commission fees.