Well, its free after you pay for your metal detector.
I have been metal detecting since 1998. I started with a mid range detector from the brand name Whites. I started off like everyone else only finding junk, digging up bottle caps and various junk metal items. The occasional modern coin made it kinda okay. Started thinking, “this hobby sucks”. I thought all the people on the different metal detecting forums were lying about all the cool old coins they were finding. No wonder so many of these detectors end up in the back of a closet.