Well, I was at this coin shop today and he had this nickel and penny cleaner to get dirt out. It smells like perfume kind of, do those lower the value of the coins greatly?
Yes that stuff will greatly lower the coins value. Only concentrated Sulfuric or Nitric Acids should be used to clean coins. Some think Hydrochloric is also good but only if properly mixed with the Nitric. for real, don't clean coins.
Another thing is coins that smell like perfume don't have much resale value. Now if he would have used Vinegar, the coins would have smelled like a salad and have a much better resale value for buying lettuse.