I don't find a plugin, where customer can pay in advanced.
The only Payment, which is similar is Payment by PurchaseOrder. But here a sreen appears, where you can put an Ordernumber in it. Is it possible to hide this screen? Or is another prepaid plugin available anywhere?
If you are a developer, you can modify one of the existing payment plugins like Check / Money Order or Purchase Order, and update this method to return true:
/// <summary> /// Gets a value indicating whether we should display a payment information page for this plugin /// </summary> public bool SkipPaymentInfo
Or, we have a NetTerms payment plugin (which we did for a client a while back, but just never put up as a product on our site). The NetTerms plugin can be configured with "Prompt to accept net terms" - "An option indicating whether to show the payment info page (terms of payment text). If checked, the customer will see the terms of payment text and be prompted to accept net terms." If the oprion is not checked, the payment info page is skipped.
If interested, contact us at support at noptools.com (and let us know what version of nopCommerce you need it for).