Vehicle parked about one at office in the city (5)
I believe the answer is:
cairo
'office in the city' is the definition.
'Cairo' can be an answer for 'city' (Cairo is an example). I am not certain of the 'office in the' bit.
'vehicle parked about one' is the wordplay.
'vehicle' becomes 'car' (car is a kind of vehicle).
'parked' becomes 'o' (I can't explain this - if you can you should give a lot more credence to this answer).
'about' indicates putting letters inside.
'one' becomes 'i' (Roman numeral).
'car'+'o'='caro'
'caro' enclosing 'i' is 'CAIRO'.
'at' is the link.
Can you help me to learn more?
(Other definitions for cairo that I've seen before include "Egypt's capital" , "Port upstream from the Nile delta" , "City near the Nile delta" , "North African capital" , "Capital of Egypt" .)