Big Stones Rule:
The largest the stone in your engagement ring the greater the percentage of retail that you are likely to be offered for it. There is a more robust market for diamonds of over 1 carat, they are more valuable, and they are easier to grade (measure the values of the cut color and clarity). If you have an engagement ring where the main stone is less than 1 ct, it is still possible for you to receive a good amount of money for your ring, but be aware that it will not be 100% or even 75% of the retail price of the ring. If the stone is larger, it is much more likely that you receive an offer closer to one of those percentages.
Solitaire Engagement Rings are Timeless:
If the engagement ring you would like to resell is a diamond solitaire, it you are in luck, because solitaires are still in style. To boil it down to nuts and bolts, if the ring you are reselling can be cleaned, polished and sold to a retail customer as is, it is worth more money to the buyer. That means that if you ring is still in fashion, there is a greater chance that you receive more money for you ring than if it is dated.
The value of your stone is only part of the equation. If your ring is a high carat gold, (such as 24 carat gold) that is part of the value of your engagement ring as well. Don’t forget to factor that into the value you would like to receive when reselling an engagement ring.
Cash is King:
You may very well run across people who make you a very attractive offer for your ring, but then want to pay you over an extended period of time. Remember cash is king and slightly less cash today is worth more than more cash later. Beyond of the time value of money calculation, do you really want to be in the business of collecting from someone?