Never had any problems parking wherever, London, Cardiff, Norwich, Birmingham, Manchester, Glasgow etc: etc: and many other cities and towns both in the UK and abroad.
As far as mpg is concerned, I would be very surprised if you got anywhere near those figures with anything but a Smart car or Twingo.
My last 4 "normal" cars never gave more than 25 mpg real life consumption around towns. On my Cali I 'm getting 30 and use it every day, not commuting as I'm retired but everyday nonetheless.
It's no bigger than many of the large cars/ vans you see about.