As a person who currently lives in a studio apartment (and has lived in them before), you want to focus on multi-purpose pieces. A bed with storage is a must. Ikea sells a lot of beds with built-in drawers under the bed, or you can buy containers that will easily slide under the bed. Great for extra linens and seasonal items. A small dresser makes a good tv stand and gives you storage. I also recommend a small shelving unit for the bathroom, like this one, this one, or this one. A word of advice: measure the room, measure the door, measure the hallway, measure the stairwell/elevator. You don't want to buy anything you can't get into the apartment or that won't fit in the space where you want it.