I need to build web application where users can sell goods. Each user should be able to get money directly on his PayPal account. Can you suggest which PayPal service/payment method (or other payment system) it is better/safely to use in this case?
Thanks in advance
This is easily set up (if I read your requirements correctly). You would have to create your part of the system, but that's obvious.
The rest, specifically vendor payments, could be handled all by PayPal.
PayPal could process the orders into individual accounts. You would simply have to use the same IPN notification file for each Buy Link. This IPN notification file is what PayPal uses to notify an order has come. It does not matter that it may have come TO Suzie's or TO Bob's account.
So, your notification script gets the order -- Then, your internal system differentiates the vendor and ... that's it ;).
IPN is very simple too, and they've got nice templates in various languages to get you started.
I'm sure there are alternate ways to do it, but IPN is what I personally use, combined with a back-end system. I even have another vendor whose plug-in for my product I sell. Money goes directly into his PayPal account by simply changing the recipient email in the Buy URL (or form).
Any competent programmer should be able to handle this with ease. The proficiencies would be SQL/database experience and web coding (any language). That's about it. A non-programmer could probably even learn, though needs to be careful to sanitize the input to protect against SQL injection attacks.
You can use ExpressCheckout, this means that your sellers do not need tho have Pro accounts, but login and payment will occur in paypal's popup window. You can also use more advanced integration, but this might require the merchants to upgrade their account, and this might cost them money in every month.
You also need to collect API keys from merchants and store them in a very safe location, or collect the money yourself, and pay for the merchants using paypal's API code, but this will introduce additional (transfer) costs.
You will most likely have to write it from scratch. I mean, from some bare framework.
来源：https://stackoverflow.com/questions/3749229/multi-merchant-payment-system-with-paypal