I don't like male dogs (for MY pets) for precisely this reason. My Pippi was a puppy mill puppy, too (I got her from a pet store before I knew the horrors of puppy mills. She was "aging out" quickly in the store, though
. I never once used pads or newspaper in my condo. I always took her out, for however long it took - at times close to 2 hrs and saying, "Pippi do a 'hurry up' - the word I was taught in her training so as to make her associate it w/peeing & pooping. She is, and has been, 100% housebroken. I feel putting paper down reinforces peeing in the house. Same w/the belly band. He needs to learn, it's not okay to urinate all over. This would frustrate me to no end. If I were in your situation, I'd hire a trainer or enroll him in some training. You don't want to strap a diaper on a 3 y/o dog and, in esscence, tell him it's fine to urinate all over your home. Otherwise, you have many years of unpleasantness (and, a urine-filled home) before you!
Best of luck! It CAN be done!