I crunched the numbers for a GIIB before...
If you want to break it down to the flight hour (I know, don't combine fixed cost into variables - but for the sake of the argument) - flight time of 150 hours/year - without setting anything aside for refurb or paint, but including maintenance, hangar, crew and other "minor" things like insurance, you are looking at close to $4,500/hr - provided you get $2,00/gal in FLL; let it rise back up to $5,00 and you are looking at $5,500/hr (assuming a fuel burn of 488gal/hr).
That said, nothing set aside for overflight permits and other international fees and other afore mentioned cost like catering and FA.
Is a GIIB with Stage III hush kits allowed in Nice? I don't know - but as you said yourself, the airplane is in its last 5 years of duty.