Quite a lot of the new alphards and elgrands have automatic curtains, push of a button and all of them open and close.
I have tinted windows but when I approach a road block I open all windows so that the PO PO can see inside and they let me pass, if you dont do this then they cant look inside and will usually pull you over and then take your details down and you will receive a letter to take your car to the Govt vehicle examination center which means you will need to replace all windows before going there so they can give you a pass report.
Ever year for my MOT i need to get my windows replaced and rent plain windows. Pain in the arse but its the rules.