There are several factors that go into my pricing of the coin rings I make.
I focus on the highest quality possible so I do spend time picking out the coin and creating the ring myself when an order is placed. Some makers hire employees to help them, which is fine, but I do not. Also, if I am not happy with the finished ring, I will start over again. I prefer quality over quantity but nothing against the makers that make high quantity, it is the makers choice. There is high demand for these rings as well.
Another consideration is the wear on the ring. If a high priced coin is purchased and made into a ring, in a very short period of time, that extra money paid for the detail may be lost as rings are worn down, scratched, dinged, etc very quickly. If worn every day and you are active, all of the details can be lost and a smooth band is left on the outside. If/when I make my wedding band, I would put the critical side on the inside of my band and expect the outside to be worn smooth as that would be a daily worn ring. A very nice coin ring with extra money spent on detail to show on the outside, gold plate, etc should be worn as a special occasion ring or at least expect the ring to be worn down.
I have been raising my price slowly over the past 11 years or so as my quality improves but also to lower demand to something that I am comfortable with. I also fully guarantee the ring. If you don’t like it, you can return it for a full refund. I also offer free resizing.
For most of my silver coin rings, I do not purchase the highest priced coin. The highest priced coins may not only be because of the crisp detail of the coin but may also be due to the rarity of the year it was minted. This is called numismatic value. A high priced coin may have poor detail but be minted in a rare year. I will hand select the coins at a coin shop with the best detail and upon a ring order, then select the best one I have for that particular year. If the year is not critical, I will select the best coin I have at the time of the order.
However, if a coin is only available with numismatic value, for example the 1 ozt platinum High Relief Angel Isle of Man, there is a very large numismatic value that is unavoidable and is added to the overall price. With this comes great risk because once a hole is punched in the coin, that value is lost until the ring is finished. If the coin is not successfully turned into a ring, that is a considerable amount of money lost so this risk is incorporated into the price.  This is the reason for the higher priced gold rings and platinum rings. Also, if a ring fails, it is more difficult to sell platinum as scrap therefore increasing the risk to the maker again.
I can also make rings from customers coins but there is a risk of a flaw in the coin or mistake on my part that would destroy the coin and not be a successful ring. This is rare but possible. If this were to happen, I would either refund completely and return the metal or attempt another. The price is the same due to the higher risk associated with the coin.
So the main factors for pricing for me are quality, price of the coin, demand, guarantee and risk associated with the coin.