John Simm (Baxter), Philip Glenister (Quinn) & Marc Warren (Rick) also worked together on State of Play (2003) as Cal McCaffrey, DCI William Bell & Dominic Foy respectively.
The first hat Baxter (John Simm) tries on looks similar to the one he himself wore in the first season on Mallorca, while the Fedora he tries on next looks similar to the pork pie hat then worn by Quinn (Philip Glenister).
At 5.05, the price tag can be seen on the underside of Christiane's shoe.