The only thing we have used, and with some good results is the Feliway disfusers. I always have one going, and 2 when it is cool enough to open the doors and windows.

Keep in mind, it will not FIX the problem, it will only help ease it. Yoshi (my pee'r) is also taking 0.3 ml of Fluoxetine every am. So between the two, it has helped.

The only time he "slips" up is during the cooler months, when I have the doors and windows open, he tends to pee even with everything But that is what we have to live with, so at least we are prepared, somewhat.