Why does Olivia say "tell me about it" in this dialogue? What does it really mean?
Sarah: Well, I was renting a room in a shared house, but now the landlord has decided to sell the house, so we all have to move out...
Magda: Oh no...that can be really difficult in London. It’s so expensive here...
Sarah: I know, I’m not sure I’ll be able to afford it...
Olivia: TELL ME ABOUT IT!
Sarah: About what?
Olivia: Sorry...I just mean, I know how expensive life is!
Sarah: Why’s that?
Magda: Olivia wants Harry to set up a website for her, but he’s asked for loads of money!