Can You Defer A Semester As A Senior For Financial And Housing Problems?

I am going into my fourth year at college but am having severe financial problems, and am not sure I’ll be able to come up with the money to spend another semester here. In addition, I’m having difficulty finding housing for next semester. I was denied on-campus housing and cannot find anything off-campus until two weeks after the semester starts.
Are these valid reasons for deferring a semester? Can I defer after already starting school, or will it count as a withdrawal? Would I have to re-apply if I want to come back to school in the spring? Have you ever hear of anyone taking a semester off for financial/housing reasons?