Not sure I have the punctuation right here. "Thing is Steve old chap, we're a bit worried ourselves. While you and I are sorting out the finances, could my friends take a quick peek in her room at all? Be ok that, would it?"
I would add a few more commas: "Thing is, Steve, old chap, we're a bit worried ourselves. While you and I are sorting out the finances, could my friends take a quick peek in her room at all? Be ok, that, would it?"
You need one more comma - there's pretty much always a comma before somebody's name when that person is being addressed. Apart from that, looks fine to me for dialogue.