zzz....took me half an hour.
just some clues:
1) when you're under the bed, theres another number on the other
side under the bed (not in view).
2) try using the knife on every place that contains a
number/item.
3) please read the clues.
4) you'll find a code somewhere. it's in wingdings font. it
translates into 39051.
5) the final key you get is a fake.