The Berretta is a fine over under shotgun. The only care you need to make is to keep a nipple pick( wire) on hand and make sure the flash channel to that lower barrel is always cleared before each loading, as it is fairly long, and narrow, and can be clogged easily. Just run the wire down through the nipple after you remove the spent cap and wipe the nipple off. Sometimes, blowking down the barrel will clear it easily, but I don't recommend this procedure as it points a gun with two barrels at something you don't want to destroy, and a bad habit can lead to an accident. If you will put a damp patch in front of a cleaning jag and run it down the barrel, you should hear, and sometime see smoke coming out that nipple- actually you should see this cleaning both barrels. The camp patch will snuff out any hot embers down there, so you don't get a surprise pouring in the next powder charge! I follow the damp patch with a dry one, to make sure all the gunk is out of the barrel, and the gun is shooting " One Shot Dirty ", each time I load and shoot it. When hunting with a shotgun, particularly a ML, I am in no hurry to load it fast, so I take my time. I also like to enjoy the scenery, watch the dogs retrieve downed birds and bring them to heel, and watch the faces of other hunters I am with watch me load that BP shotgun. They are like little kids in the candy shoppe. So, take your time and load it correctly, and it will serve you will. Like all double barreled guns, you will have to spend some time working up loads on paper, and finding out where each barrel prints its patterns. With some guns there are different loads for each barrel to gain maximum performance. That is just part of the deal.
You have a very good gun, and I know a lot of shooters who would jump at the chance to buy one for only $200.00.