Tracy, a first-year law student, needs a place to live for the rest of the spring semester. She drives past an apartment complex that advertises "rentals by the week or month." On January 6, she visits the apartment manager’s office and speaks with Sonny. Tracy tells him that she needs a quiet, comfortable apartment "for a couple of months." Sonny shows Tracy a spacious one-bedroom unit that’s open, which she agrees to take. They agree to a weekly rental of $200, and she moves in the next morning. Tracy and Sonny do not sign any writing or document. What sort of leasehold does Tracy have?