It was fairly straight forward. I originated from and then returned to Spain so had to clear customs before leaving Spain and then on arrival back in Spain afterwards.
Handling was done through Gibair and cost around £120. This covered the landing fee and parking, although I am not sure how you long can park for before they would start charging extra. I gave them a call the day before to give them a rough time of arrival and they were there waiting for me when I landed.