If it is any consolation, I have a similar problem. Huey is almost 5 and he has peed my entire house. He pees outside and gets treats every single time. (I have to make sure I see the evidence, because he will fake it to get a treat) He poops outside, too. We have the poop down to specific times of day with his feedings, but sometimes he likes to throw in an extra one indoors to keep us on our toes, I guess. Also, as a nurse, sometimes my hours are erratic, so sometimes it is my fault if I am not home at designated poop times. Since he eats dry kibble, he makes tootsie rolls, so picking up the poops is not an issue for me. The pee is, though. No matter what I do, how many times I take him out and no matter how many times he gets a treat for good peepee, he is still gonna pee inside at least once if not 2 or 3 times daily. The door to the deck (his designated potty area) will be OPEN and he will pee on the kitchen garbage can or the dresser in the bedroom, or on a multitude of other areas in the house. I have scrubbed, sprayed natures miracle, sprayed no marking spray and left down pee pads, all to no avail. I have finally resigned to keeping down pee pads in the most peed upon spots, just to keep the hardwood from even more damage than it already has. I think I should own stock in Swiffer and natures miracle, as much as I use every day. I have pretty much given up, because like my husband said, "you're not gonna get rid of him, so just deal with it". I still try with the treats and frequently running him outside, but I pretty much have resigned myself to daily mopping & playing "search for the pee spots", since he likes to change it up frequently.
I do have several belly bands that we use when visiting other homes, because he will mark new placee. I got him neutered at 6 Months old and that made very little difference in his marking.