Option for auto Masspay in ubercart marketplace
Automatic mass payment (with paypal only) 

Explanation:
When a user makes an order and pays with PayPal or does ExpressCheckout with PayPal and the system redirects him to "checkout/complete" the added code starts to work and makes masspay for all the orders done before that one. (Newest order not included)

Another Method :


Go to Test Accounts, select "Create Account: Preconfigured", Choose
account type "Seller", use given data
Go to API Credentials, copy API Username, Password, and Signature to
Drupal Enable uc_paypal module
Setup PayPal Website Payment Pro settings at: "Store Administration


  
    Configuration >> Payment Settings >> Edit >> Payment Gateways" or directly via /admin/store/settings/payment/edit/gateways
  

Enable this payment gateway for use API server: Sandbox
Now enter your API credentials
If IPN is setup you may now make payments at "Store administration >>
reports >> Seller reports"