In many cities the apartment rental market moves fast and landlords can be picky about who they want living in their rental. If you are hoping to move into a new apartment you may want to consider having something typed up called a renter's resume.
A renter's resume is kind of like a resume you would have when applying for jobs, but instead of past work history you would have past rental history. You may also wish to include letters of reference from past landlords or friends who can vouch for your character as an apartment renter. In competitive markets a renter's resume may be just what you need to get the landlord's attention, thus helping you rent that beautiful apartment you have always dreamed of.
If you don't have a past rental history, write a letter explaining how responsible you are, your work history and give some references from people who know your character and turn that in. It may give you an added edge over someone who doesn't have anything at all.