I am also in an apartment instead of a house for a similar reason. To make mine look more like a house, I put curtains up over the miniblinds that come to the floor. I just bought some earth tone sheets and hund them on black iron look rods with black metal clips. I also use almost floor to ceiling bookcases. I like the craftsmans look of an older house with modern touches so I try to duplicate that in an apartment. I like natural paint colors on walls and white trim and doors. For color throughout, add red , purple, mustard, etc. in things like throw pillows, candles, throws, pictures.. I also use iron wall sconces that hold candles. About the AC. I have one tooo. I have a deep red roman shade over mine, but almost floor to ceiling cutains would might work. Make it look like you have another window. Make sure you match it to other windows in the room.

I had a friend build a four sided box that slipped over the unit and attached shutters to cover the front.