Turning a 2 seat Piaggio in a 4 seat

Dear Forum,

I am new here and I am currently looking for a used Piaggio Porter. I would like to be able to have 4 seats but most Microvans are 2 seater transporters. Is it possible to convert a 2 seater into a 4 seater and what do I need? I figured windows for the back row, as well as a back row haha and seatbelts. Is it possible to put all those things and where do I find them cheap?

Thanks already!
Kea

You can do it but fraught with problems such as seat belt anchors etc., insurance due to change. I would hang on for one to come up that was a multi seat from the factory then all issues solved for you.

I think all of them have all the captive nuts in the bodyshell for the seats and belts from memory.