A friendly greeting--'buddy' means 'friend'.
This expression is becoming more common in US English. In this case it means 'Fine' 'OK' 'I understand'. It is also used as a response to 'Thank you', i.e. it is replacing 'You're welcome' especially among younger people.
e.g.
A) "Thank you"
B) "No problem" (Younger person)
"You're welcome" (Older person)
In colloquial speech the verb 'to be' is often dropped. In standard speech this would be "Are you here on business?"
An idiomatic expression meaning "that's (very) nice for you".
'fella' = 'fellow'. A very direct form of address. The cab driver is slightly annoyed at Takatori's mistake.
US dollar bills are all the same color and all the same size. The only difference is their value:
$1, $5, $10, $20, $50 and $100 dollar bills are in common use.