In the coffee shop, Jerry and his friends discuss someone's rent-controlled apartment. "50 years...they pay $300 a month." Later, there's a scene at the funeral home where they try to convince a grieving spouse to let them move into the apartment.
Jerry lives in a rent controlled building. The only time an apartment opens up is when Mrs. Hudwalker dies, because rent controls create immobility. Elaine and Jerry find out about the opening, and because Elaine happens to be first in line, she gets it for $400 per month. Subsequently, Jerry gets worried about having Elaine living so close, and tells Elaine that she can't have the apartment--the super was offered a $5,000 bribe.