I am using Enterprise Duo to list on eBay and Amazon. Even though I have no problem paying $99.99 per month, I must say that the pricing is not reasonable. The Enterprise version should include both eBay and Amazon accounts. For people who only sells on Amazon, the only option now is Enterprise Duo, that’s a high bar for those who never tried SixBit before. If I were an Amazon who never tried SB, I would be hesitating. I guess most people who use SB for Amazon are already an eBay seller.
A more rational approach would be like this:
Home & Hobby ($19.99): eBay only
Small Business ($34.99): one site (eBay or Amazon)
Enterprise ($69.99): eBay and Amazon
With the coming of Etsy integration, SB can add more option to each version and use the highest price tier ($99.99) for all three sites.
(Been on eBay for 16 years and used this software in the days when it was still called Blackthorne.)