Now I see the source of confusion. I think $100 from the perspective of a tenant may be quite a lot (as mentioned a 12.5% increase). However as you said my thesis is from a landlord's perspective $100 is insignificant with all things considered. If even one unit were empty for two months, that would be an annual loss greater than the extra money they would make from the previous tenants. Also in our case they already have had a unit empty for over six months now which further baffles me.