I'm sorry to hear that you feel that PayPal didn't help at all, but you have a lot of resources at your disposal. It seems that you simply did not ask the right person or asked the right questions. Customer service for large corporations is difficult to get through, but PayPal has a lot of people who could easily answer your questions.
I always say this, although I'm not sure how many times in this forum: In PayPal you can do whatever you want. Give me your idea, I will give you the way. Whatever you do, you can do it with the right coding.
You can use the Website Payment Standard (WPS), and you only need your seller’s email address to create the buttons that go into their account. (set business variable)
API- Website Payments Pro (WPP) Express Checkout (EC) , PayPal API . ( subject , API )
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