I had Jake (Sheltie) completely, 100%, housebroken within about a week. He was about 10 weeks old at the time. I don't know if this method will work with other dogs, but you could try it. I was very proud of myself for coming up with the idea, and of Jake for training so quickly.

I got him when I knew I'd have a lot of time off work to train him. When I brought him home, I put a leash on him and hooked it to my belt (I don't usually even wear a belt but I got one for that purpose). Every single second that he wasn't in the crate, he was directly in my sight. I watched him very carefully and as soon as he'd squat or lift his leg I'd yell "Outside!" That would startle him enough that he'd forget to go, I guess. Then I'd pick him up and run outside with him, or run as fast as he could go on the leash, and when he'd do his business I'd praise him immensely and give him a treat.

He only actually went in the house once while I was housebreaking him. I had him on his leash, attached to my belt, and I was ironing something. I took my eyes off of him and he peed on my foot! I just yelled "Outside!" and ran outside with him even though he'd already gone.

He did have a few lapses in potty training later. I got him in the winter, and we live in a very cold and snowy climate. When the snow thawed he was VERY confused about using the bathroom outside. So - I started the same training over again and had him retrained quickly.

Years later. I had rescued a little mixed breed from the shelter, and she seemed housebroken but she went both #1 and #2 on the staircase a few times. She, unfortunately, passed away about a year ago. Just a few months ago Jake started going both #1 and #2 in the exact same spot Pepper used to go on! I don't know what the deal was - he'd only do it at night while we were sleeping.

My husband was insisting that we find Jake another home, but I solved the problem by having him sleep in the mud room at night, with the door shut so he can't get inside the main part of the house. Jake was already in the habit of sleeping there, so he doesn't even mind. His food and water are out there, so he won't use the bathroom there.