Examine the package in a hurried fashion, though careful not to rip it. Check it's weight and guess at it's dimensions. Also shake it slightly to hear if something rolls inside of the package or if something tings against another something. After checking the package guess if it'll be worth keeping and opening later. (the picture IS in a frame right?) If so examine the frame, guess at it's value and if you think it's worth more than 40$ steal it. If it's too big leave it. Check Under the mattresses and bed frames for anything valuable. Look around the room more, and IF it's too dark carefully feel the floor for furniture legs. After locating any furniture check for hinges with which to open drawers, when found open the drawers and search for a wallet. After searching the draws take a peek outside the door, if someone's coming run to the window and try to open it as quickly as possible so you can make a daring escape to the roof. If no one is there leave the house, and keep the clothes.
If someone enters while your in the room, say something along the lines of,"Hi, I heard a noise in hear and came to check it out. I found nothing though, there was this open chest. I just looked into it to see if anything might have been missing. I think there is some stuff missing but I wouldn't know." If they don't believe this say, "I have to go to the washroom. Please let me." And if they don't pull out your knife and dash across the room to grab them, hold the knife to the person's throat and threaten,"IF you tell anyone I was here I will send my friends to rip your guts out." Kick their legs so they fall and run down the stairs and make a noisy exit outta the house. IF you are unsuccessful, just RUN. Running through the window is not an option though.