Well, I will agree with Rachel, he is a very good boy. My only suggestion would be, if you do not want him to go potty anywhere in the yard but "his area", then don't let him anywhere else in the yard until he has done his business. That means that every time you want him to potty, you put him on his leash and walk him in that area until he relieves himself, you praise him, and then he is allowed access to other areas. You may want to teach him a buzz word like potty or something for when you are in a hurry. But you (or other designated adult) should be the one to take him there and teach him that is where he is to go before he has access to the rest of the yard, and not just let him wander around and decide for himself. If that doesn't work, you may want to fence off an area of your yard of him to run and play and potty without concern for plants and grass.
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