Next Steps: Software to Allow Stores to Accept Steem

Yesterday I talked about an idea to get Shopify stores to accept steem currency. 

The basic concept is that if we could get stores to accept the steem currency as a payment method it would have a huge impact on the currency valuation.  

And it would add a lot of value for the users.  People could use it to buy stuff! 

@jerrybanfield suggested that I look at Changelly.com as a solution to change the steem dollars into bitcoin.  Then change the bitcoin instantly into USD.  And it is this USD that is deposited into the Shopify store's account. 

Today I sent off an email to Changelly.com asking a few questions about their API. 

The main concern right now that I have is how to minimize the transaction fees.  Because there are multiple steps to go through and different sites are taking a cut.  

What do you think is a reasonable percentage that people would be willing to pay to be able to purchase something with steemit on a Shopify site?  (including all costs)