Need Advice on Gold Selling Business

I am planning on starting a gold and account selling shop here on sythe. Currently, I can make a good gold shop and account shop fairly easy, however, some gold sites have are custom coded. This allows for a lot more flexibility in payment options and other things.

That being said, what is the meta for these businesses in terms of payment processing, dashboards, and what not.

One interesting thing I found was selly.gg , but it isn't as user friendly as I would hope.

What are some good tools and implementations gold sellers use to help keep business running smoothly.

How are some gold sellers able to accept multiple different currencies seemingly easy.

Looking for someone to point me to the right direction.