Personally, I would pick a room with a non-carpet floor, ie. Laundry room. Put Sara the dog and her bed in their for night time; so if she poops over night, it will be easier to clean. If she cries, you can think about putting a 2nd dog in their with her so that the Laundry room seems more like a room than a cage.

As for pooping outside, the best command next to "come here" is the bathroom command. I take their favorite treats in small pieces with me on walks (especially in the morning when the dogs first wake up and after eating their dog food). When the dogs go pee, I say "Bathroom Here" and then give them a treat. When the dogs go poop, I say "Bathroom 2" and then give them a treat. I try to use the same word "Bathroom" for both pee and poop so that they know that potty functions of either pee/poop on command gets a treat. Depending on how smart the dog is, they'll learn the command within 1 wk to 1 month so that they know to pee/poop on command.
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2012 Specialized Amira Elite, upgraded carbon handle bars, Jett saddle 143mm switched to 145mm 2012 Selle Italia Max SLR Gel Flow saddle
2010 Santa Cruz Juliana with R kit and Crampon pedals
2011 Specialized Ariel Sport,suspension post,Serfas Rx Women's Microfiber saddle (sold)