Mouse joke

A: I'm in a big trouble!
B: Why is that?
A: I saw a mouse in my house!
B: Oh, well, all you need to do is use a trap.
A: I don't have one.
B: Well then, buy one.
A: Can't afford one.
B: I can give you mine if you want.
A: That sounds good.
B: All you need to do is just use some cheese in order to make the mouse come to the trap.
A: I don't have any cheese.
B: Okay then, take a piece of bread and put a bit of oil in it and put it in the trap.
A: I don't have oil.
B: Well, then put only a small piece of bread.
A: I don't have bread.
B: Then what is the mouse doing at your house?!