When I started my HK company I had been living in Asia for several years already and it just made more sense due to the lower effective taxation.

Card processing: Braintree, 2Checkout, and then some lower tier options like PaymentWall. I'm not including old-school/direct merchant accounts here. Keep in mind that 4%*$0.45+1.5% is totally standard, with that final 1.5% added for non-HK billings. So you will pay 2% more to charge a card in HK compared to US. But your tax rate can be literally zero percent.

A better option may be a US subsidiary or a US company wholly owned by a foreign entity. This is something I am considering, because...

> banking

Absolutely everything is a pain. After four years I still don't have a business charge/debit card. Applications for card processing and debit cards each take dozens of forms and generally longer than a month.

Having said that, I have saved lots and lots of money.

Lastly, a HK company costs about $1,000 to setup and $2,300 yearly to maintain.