I can't chime in on any potty training tricks as my dogs were super easy to potty train but I do have a recommendation on a product for your soiled carpets and cushions. I babysit my husband's ex boss' dogs and we own a very expensive rug that her dog decided to mark territory on. Of course, that then made my dogs mark OVER her territory with their own urine and it was a disaster. The rug looked and smelled horrible. I bought this and SOAKED and scrubbed for like 10 minutes and let it sit for an hour and then wiped up the excess liquid. It took a full 2 days to dry up but that area looks brand new and best of all, there isn't even a HINT of the smell of urine on the carpet. I will warn you though, the smell of the product is very strong and lingers for about a week after but then disappears. Good Luck!
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1