Y accepted 18 transfers last fall and 24 the year before, it just depends on how many students leave and what the housing situation is.
It really helped her to attend the Focus program the week before school started. She met many other transfers who seem to be the core of her social circle. Her suite placement was good but not great, that's kind of just the luck of the draw for transfers I think. She's met other people through classes in her major, as well as clubs and other ECs.