An apt -- as in an apartment? I Googled it, and the one youtube video I saw looks pretty cool. This is what I was looking at:
They say that when you have setbacks in housetraining to go back to the beginning and start over.
By the "beginning," the advice I like best says limiting their freedom. I did that by setting up a 10 foot x-pen, with a bed on one side and potty area on the other. It provided more space for playing and about the same amount of space as the video for pottying. My pup stayed in the x-pen at all times that I wasn't directly supervising -- in other words, overnight, when I was at work or any time I was too busy to watch her directly.
I let her out at predictable times -- 5 minutes after meals, first thing in the morning and immediately before bedtime.
The apartment (if that's what you're getting) looks like it could work. If not, consider giving the pooch a little more space.
I personally don't like belly bands, but use them if I'm visiting someone else's house, where my male is more prone to marking. For home, I manage it with the X-pen.
Good luck!
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Mike ~ Doting Dad to Jillie, Harper, Molly, Cooper, Eddie (RIP), Lucy (RIP), Rusty (RIP) and Jack (RIP).
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