It seems that it relates to aircraft acquired via brokerage although I am not 100% sure.
In view and buy view
42108 1 Boeing 737-300 €33,095,767
but won't allow 42m selling price because in for lease view:
Open Market 42108 Boeing 737-300 €28,484,808 €1,780,000 36 months
It probably takes this 28m value not correct 33m to calculate max price.
