Implementing marketplace in classified drupal theme

It’s a short description: please read it all before to send offers. I’m building a marketplace website with drupal, the layout and template is already done, also most of the modules needed are already there. I need someone to complete it: enable the checkout function and allow users to pay other users within the platform with a commission of the payment goes to the website owner. So, user x pay 11 euro for service offered by y: 10 goes to user y and 1 to the website paypal account. (no need to set shipping,ect.). So, there is the need to implement paypal and checkout. Now the website is based on premium flatclassifieds theme with commerce and ad classified modules, among others. I estimate in total less than 3 hours of work. That’s a proof of concept. I have a lot more work upcoming so that’s also a way to find a long-term collaborator if we work well together.