[smithlane]

So sorry, I have only just seen these replies!
Thank you again everyone, I have decided to keep the car only because we will be visiting my friend in Columbia on our way to DC from Philly.
Once we reach the hotel the car will be left in the car park until we leave to drive back to the airport so will just stump up the hotel parking fees.
At the moment the trip isn't looking very likely but the balance doesn't have to be paid until 3 weeks beforehand so anything could happen between now and then!
If we can't get there we will definitely rebook for later in the year