Sandman pretty much said it all. In my case, if the person calls me right from their blanket in the dry sand at the beach, I'm currently 100% on those. Yard searches, about 85%. Lost a month ago in the surf, it's less than 25%. So much depends on the circumstances, how long the item has been lost, Private or public search area, and most importantly, whether there is more than one possible area where it could have been lost. In many cases, they don't know that. They remember having it at one point and later discover it's gone. They may have been in many places and done all kinds of activities in the interim. Some of these areas just aren't searchable with a metal detector, such as shopping malls, inside a store, or many other paved areas. Other than adding another set of eyes to search, having a metal detector is no extra help. The equipment needed is based on the item and search area. I currently have 13 detectors. Some are better at certain searches. A small gold earring stud and I use my Goldmaster Vsat, out in the surf and the Excalibur gets the call. Dry sand and yards, the E-trac is my first choice. Coil selection is another factor. A junky park you might need a small coil. A huge soccer field and a huge coil can save you from a long and hard day of searching. You need to start with a good detailed discussion with the person who lost the item. Narrowing down the search area and getting valuable details of how it was lost can significantly increase your success rate.