are you able to take him outside. Our vet suggested that with a yorkie as with any small dog, who are harder to potty train, and they have their "terrier" attitude which I LOVE, she suggested either pads or outside, but not both and I've had dogs my whole life and started training from indoors in a pen with papers transitioning to outside. That said i decided to take her out every 20 minutes until she relieved herself, its physically draining, but it pays off - eventually depending on their personality. Mind you they still slip up but she's 95 percent trained and with her thats the best I can do. You can also keep her on a leash with you while you are walking around the house, until you are ready to take him out, also invest in a crate, they don't like to go inside their crate - a crate big enough to lay in without extra room to allow elimination good to use when you're not home or doing something where you can't watch them. Hopfully you can find a cleaner at a pet store that eliminate the smell from the arm of the couch, and discourage him from sitting there. also the bissell bio spot pet remover vacuum is a very good investment, best thing i've used to clean carpet stains with.
Sorry so wordy, hope this helps other wise establish a pen with pads and have a crate when you cant watch him. Use the same command to have him eliminate and praise, praise, reward when he "goes"
hope this is somewhat helpful.
