Hi,
We're happy to help when people have issues. The forum is filled with answer from us on how to customize things.
However, you need to understand that developing a payment plugin takes between a day when all goes well and the integration is really easy and the documentation is concise and clear to weeks when it's complex. Asking 450€ for such development is quite normal and I think that it's even not that expensive. Would we do it ourselves for one client, we would charge that much.
We can only afford to charge a lot less than that because we except selling many of them when we develop them ourselves (and so we do that when we've had enough demands for it).
I doubt that the developers of Eshop will develop any plugin asked because someone requested it.
I'm sorry but we can't develop all the possible payment plugins in the world. There are hundreds of payment gateways and they even change their APIs every few years. So it's a lot of work to just maintain the ones we already support and we prefer focus on core functions of HikaShop rather than plugins any PHP developer can do.
We provide a list of partners so that you can easily find people to work on such development, but any PHP developer can work on such payment plugins. We provide the developer documentation on our website (
www.hikashop.com/support/documentation.html#hk7
) and with the integration documentation and a test account from the payment gateway, any PHP developer should be able to do it.