I have a new family of 3 transitioning . They have always had a nanny ( I see issues but a whole different thread ) my established dck were all going down at the same time but adding the new family destroyed the first nap . So I started 15 min intervals , the youngest goes down at 12:45 and 15 min my youngest new dck , goes down and so on . I have pulled one dck out to the hall as she has started going around waking up others ! Ugh
I have 2 non nappers who lay with blankets and watch a movie as well as my child .
I think with the layout of your home I would def want them both in a room so I would try them together . Also invest in a white noise machine ! That way you can move around in the other room and they won't hear your every move .
I think by using a set place for sleep and a set place for play , will allow the children to understand , this room means we sleep !!
Good luck !!!!