Character mistake: Florence grabs the victim's phone with a tissue to avoid leaving prints...but then uses her other bare hand to go through her messages via touchscreen. In many other scenes she's just seen wearing latex gloves. (00:12:30)
Character mistake: A computer display of currency transactions shows the word "withdrawal" spelled as "withdrawl." (It is also spelled correctly higher up on the display). (00:25:05)
Character mistake: The forensics report in its first screen displays the word "antybodies", when of course it is "antibodies" (00:25:15)
Answer: Most likely they had only tropical exotic drinks, he wanted an old fashioned English beer.