Know thy self
Before you hunt, articulate what you want. Are you living alone? Do you have a roommate (or two or three) lined up? If so, does everyone want his or her own bedroom? Is one roommate willing and able to pay more for a bigger or nicer bedroom? Is it more important to you to have a great bedroom or a cool common area? Do you eat at home enough to want a well-equipped kitchen? How much storage do you need? Do you want to be able to have pets in your building? Do you want to live in a small building in a family neighborhood, or a large elevator-building more towards downtown? Would you sacrifice a good location for a fantastic apartment? What's the maximum amount you want to spend on rent?

Answer these questions and figure out what else you need to be happy in your new place. Then, hold a summit with your roommates. Negotiate this stuff before you go out looking so there are no awkward moments or heated debates when you're running around with the realtor or hauling your grandma's old 20-ton sofa bed up four flights of narrow stairs.