Lot of antique markets, and flea bags all over the area.
This site gives a good listing but as you know a place could have several pieces one day, and be gone the next, depending on traffic. The one in Beavercreek isn't the worst place on earth, and it is certainly close to the center. The good thing is you will be right on 35, and you can travel that out to 71, or come back toward 675, and go up or down to hit 70 to the North, or 75 to the South, so travel to anywhere in the Dayton area is easy due to Interstate avavilability.
Down closer to me off 75 at SR 63 there are 2 large complexes with fleas aplenty, a good amount is junk, but sometimes there are some nuggets. Both charge a small admission though.
Traders world and
Treasure Aisles are on opposite sides of 75, and there is an outlet mall right across from Traders world if there are any Ladies along.
Unfortunately some of the big doings are a week ago, or a few weeks away. I tried to look at auctions in the area, and I didn't see anything worth standing around for a long period of time. Richard is the "Estate sale" King. I confess I couldn't find one if I had a spyglass, perhaps he could look to see if there was anything with any promise?
Let me know if you see a place you want to check out for the quickest route to get there, or possibly a warning, Don't go there