Understandably, you may need to take the van through tolled roads.
Hirers are to be responsible for their own toll charges. If there is a toll barrier the hirer will pay the toll. If there is no toll barrier the hirer should pay the toll charge in advance. If this has not been paid, it will be deducted from the bond.
If you are travelling to Europe, you may want to arrange a European E-tag prior to the hire.