He still haven't paid me yet and I hadn't that great of an experience with this person, he has a business with developers but seek freelancers for working at internal projects, it's messed up pretty bad, almost wanted to drop it after seeing the code.

Also, he's the business owner and he's the one that don't want to pay extra taxes...

I thought of charging more, but I'd rather just end it fast and forget all about that idiot.

NoStranger

Word of advice. Set your terms with clients before you get paid. And figure this stuff out long before you agree to something. I would never accept a payment in a currency I didn't already have a plan for exchange. And I would know the cost in time and money for the exchange. I've worked with clients for many years and you have to stand your ground. Sometimes large clients have company rules they can't change but that doesn't sound like the case here.

You could charge a fee for the trouble to encourage use of bitcoin for fiat or Eth

bitcoin

Help swapping Ethereum to Bitcoin?

Word of advice. Set your terms with clients before you get paid. And figure this stuff out long before you agree to something. I would never accept a payment in a currency I didn't already have a plan for exchange. And I would know the cost in time and money for the exchange. I've worked with clients for many years and you have to stand your ground. Sometimes large clients have company rules they can't change but that doesn't sound like the case here. 

You could charge a fee for the trouble to encourage use of bitcoin for fiat or Eth