Many people still have obsolete coins at home. Some have old, royal, from grandmothers-great-grandmothers left over, others - recent, Soviet times. And, probably, many at least once, but the thought came that they are worth something, and it would not be bad to sell them.
Disused coins have a value, like any other item. The main criterion that determines the price of a particular specimen is its rarity. It is difficult for a non-specialist to determine this.
Most of the Soviet coins are practically worthless today. However, some of them are of interest to numismatists. You can sell coins in different places. Try to find out if there is a numismatic club in your city. Appreciate what you have in advance. On the internet, you will find coin price tags, tips for selling, and a lot of other useful information. True, cheap copies, most likely, will not interest anyone. But if you find yourself with a coin worth more than $ 100, then there is a buyer. Offer to buy it to collectors at your local numismatic club. In this case, the degree of preservation of the rarity plays an important role. Clubs and circles, however, are not everywhere.
Coins can be sold at an antique store - this is a fairly common opinion. But it is only half true. Stores do buy coins. But only the old ones. They are not interested in the Soviets.
The Internet will come to the rescue again. Find special numismatic forums for collectors to communicate. There you can offer your coins.
There are also online auctions. You will most likely be able to find out about them on the same forums. A little subtlety - in order to sell profitably, you will need to raise your rating. In other words, you have to buy something first.
By the way, every collector has a corresponding rating. It is expressed in conventional units and is available for review. You can find out how many deals a potential buyer had and how successful they were. This will ensure that you receive the payment due to you.