Kobe will be 5 months in one week and has been house trained since he was 4 months. I brought him home at 12 wks. Kobe also would spend time outside and come inside to pee.I found out during his training period that if i was not able to watch him every moment then he would be in his crate that was just big enough for him to lay down and turn around. If I came home and he wouldnt go pee outside, then he would go back in the crate till I let him out to go pee. So once he did what I wanted him to, he got to stay out of the crate and have time with me. Plus he would get a treat and lots of praise. I never used pads, or paper. O I think teaching him tricks at 13 weeks was the key too. He realized that when he did what I asked he would be rewarded. By the time he was 14 wks he could sit, shake, high five, sit up, lay, roll over and spin. I noticed he started doing better about using the bathroom outside. At 4 months I put a bell on my sliding door so he could hit it to alert me he was waiting by the door. Once in a while he will have a accident near the door usually, and that was my fault cause I was not paying attention to his needs.
But basically, I found that I had to be consistent with keeping him in the crate till he figured out that he had to pee when taken out. Kobe does not like to go on walks, he puts on the breaks so I have to carry him and then he will walk on the way back home. He has never used the bathroom while on these walks, but will once we are home in his own yard. Crazy.