Is he neutered? Have you ever thought of getting a belly band for your little marker? You can get them real cheap on most of the members websites. I got some from Rena at
www.barkindogclothes.com for my friends boy dog. They work perfectly. I wouldnt recommend giving him full rein of the house anymore. I would recommend only letting him roam for a short short while right after he goes potty outside, otherwise, I would have him in the kitchen or somewhere where the clean up is easy. At least until he learns where he can and cannot pee.