Her time is up

In the past, we've used a sleep training method with out kids. It's worked out just fine. Eight was the worst, we didn't know what we were doing. It took a week. Seven, he was a text book baby all the way. It was three days, 30 minutes, then 15, then 5. I waited until Five was older due to moving. She too was easy. I've made a few attempts with Baby Girl, but no luck. I haven't followed through very well. Tonight has put me over the top. Tomorrow we will sleep train. The problem is I have no where to do this. In the past, we've always had the baby in their own room. With Five, they were all in the same room, but babies themselves at the time. Didn't phase them one bit to have her cry, the boys slept right through it. She knows every sound in my room. She knows the creak in my bed and in the doors. My only option would be to move a kid out of their room. This disrupts the kid. They have school and are established in their room. N has been displaced since Baby Girl has been born. My solution, to displace myself. If we take our mattress out of our room, she can sleep train in there on her own. I'd have to have N's clothing out for work the next day. I think we will give it a try. What can it hurt? We need a 4 bedroom house. I am convinced more now than ever.