It would be nice BUT You can't keep it. You must do your best to contact the owner or the authorities. Some people think that if the Post office delivers something you didnt order to your address that they can keep the item. That's theft and the item must be returned or paid for. Now if they must access your property to get their lost drone, Well...there is nothing in the law that says they have free and unfettered access to trespass on your land.. You can even charge them a fee if you like. but it can't be ridiculous or a judge will throw it out.
I really wouldnt charge them I suppose, but it would be fun to make the Recovery team sit thru a "safety meeting" before they were allowed access to the property..Maybe even make them wear protective gear, like some chemical resistant animal costumes.maybe tie a balloon to ya so I can keep track of you. You know for Safety.