first, have you thought of removable wall paper? go to spoon flower if you can afford they are all hand designed. can even design your own.

let me know i have lots of other ideas, this would be your fastest.

The bed dominates the room and it doesn't look like there is room for more furniture. Therefore, I would focus on the bed and get some beautiful linens/pillows ... Something that goes with the paint. Don't spend a lot on decorating touches that you'll leave behind should you decide to move. Then find a couple of matching items ... vase, etc. Looks like you have lots of storage so you should be able to keep the room looking tidy and uncluttered. You might be able to place a small rug beside the bed. It's hard to beat luxurious linens ... let's face it, we spend most our time sleeping in our bedrooms.

Right now there is no softness in the room- it has a bit of a commercial feel to it. If you are allowed I would paint the walls a soft peaceful color . Sherwin Williams rain washed SW6211 is an excellent choice. Also, if it is in your budget I would purchase an inexpensive valance for the window. The wall color change, plus adding the extra softness to the window will help.

Paint wall behind bed something like this, to compliment sleek furniture. Can't paint? You can buy cheap cheap insulation panels at Home Depot that cut with a straight edge. Join with masking tape to make a 'wall'. Go for this design. Bedding now can be white with a colorful rug or opposite- white shag rug with bright bedding!