Well, an update. I stopped by about 3:45 in the afternoon, there was one guy working a backhoe finishing up some work. I politely apologized for bothering him and asked if he minded if I scanned the area after he was cleared out. He said, "Well, I don't own the property, but there are no signs, and nobody is going to care if you're here, so I don't have a problem with it. I finish at 4, so come after that, and wear boots (nails)" (Good enough for me). He also said his buddy detected this and a few other properties with no luck.
Now the property is a pretty large one, a few acres (many more acres of farm field, too). And the house and barn only covered a portion of it. So I was hopeful.
But all hopes were dashed. I spent about 90 minutes moving around the property into the little yards / fields around the house and behind it. I found absolutely nothing. Not a single coin or relic. And his buddy didn't leave a lot of dig-holes, so he didn't dig much either. Must have been cleaned out years ago. Now if I had many hours to spend there, I'm sure I could have found SOMETHING old. . . but there wasn't enough to keep me going back.
But, it didn't hurt to ask, gave me the 'permission' I needed to give it a try, and glad I did. Because if I didn't, I would have been complaining for years that I missed out on all of the coolest old coins and relics I could have imagined. Didn't need that weighing on my conscience.