On this side of the Pond, and waaaay out in the middle of the country away from big cities, 40% to 50% is pretty common. Some places will buy to stock their shelves, but most want you to maintain the inventory at your own expense/time. The take stuff in to sell "on consignment". But there are some places that will buy from you at wholesale, for retail sale in their shop. It all depends upon what you make and what they see as a potential market.
But there are always those places that view anything you made just like all that cheap cr*p imported from India, Pakistan, or Red China. They want your quality workmanship, but at that "junk" price. Plus, more than a few think you actually did import it instead of make it, and they want you to chop your price down to barely above what they think you paid to import it (excluding the cost of shipping also).
There are good places and there are lots and lots of "junque" shops - in both what they sell and what they might buy. In the end, it is often better to sell direct - either at some sort of event or farmers/craft market, or over the internet. It takes lots more time, but you can usually get a better final price.
No VAT over here, just a "manufacturer's" tax if you make enough, or that Sales Tax at the time of the final sale to a customer. And that Sales Tax gets paid by and collected from the customer at the time of the sale. Or the seller gives an after-sale discount to the customer by paying that sales tax themselves. Current for Iowa is 7% sales tax.
A GOOD consignment retail store will work with you. They will "work" to earn that commission of 40-50%. But too many have an "I don't care" attitude. When you find a good shop, do your best to work with them. You and they both should be able to be happy with the deal you arrange.
Just my humble thoughts to share. Take them as such.
Mikey - yee ol' grumpy blacksmith out in the Hinterlands