What is "made-to-order jewelry"?
Made-to-order jewelry is literally jewelry created based on an order or request. It is common to purchase jewelry displayed in a showcase.
On the other hand, made-to-order means you select stones in a loose form and make it into jewelry. You will be able to have your own "one of the kind" jewelry.
Is it expensive to make jewelry to order?
It depends on what you make (design) to determine if the made-to-order jewelry is expensive or not.
If low-price jewelry has a less finished quality, that jewelry is rather "expensive". If high-price jewelry has a finished quality, that jewelry is "not expensive".
There is a wide quality range in make-to-order jewelry. It takes at least one month to design something relatively simple; it normally takes about two months to design jewelry. Having the best quality in everything including design, material selection, arrangement, setup and finalizing, will not make the jewelry inexpensive.
The question is where and from who you order the jewelry. This will make the cost different. My recommendation is to order the jewelry from jewelry makers or designers.
What is "resetting"?
Jewelry resetting means to remake your own stones or jewelry into a new one. Making a claw ring into a modern fashion ring is an example of resetting.
Is "resetting" inexpensive?
Like make-to-order jewelry, it is difficult to determine if resetting jewelry is expensive or not. You could probably remake your jewelry at a relatively reasonable price. Some may think that remaking jewelry is not expensive. If you seek high design or quality, it may become expensive.
However, if you use ready-made (mass-produced) jewelry and remake it with your stone, that could be relatively inexpensive.