Can anyone suggest if I should be driving a minivan w/ 7 passengers inside- Paris/Florence/Rome or take public transport?

A better title might have been something like "Parking/driving in Paris/Florence/Rome?"

And my answer would be no, you do not want to drive a van (or pretty much any other type of vehicle) in any of those cities.

If you must, you can drive to each city and then pay to park the van, preferably on the outskirts somewhere. You would still then be using public transport and/or walking to get from one place to another within each city.

You could take a chance and drive in Paris, I have but you will not park in Paris. It is not possible. If on the off chance you think that you have a parking spot in Paris, when you come back to your vehicle it will be blocked in on all four sides.

Is driving in these cities any worse than driving in and parking in New York City??

In the sense that none of them is grid-like, as Manhattan is - that possibly you can't read signs as quickly - - and the ever-present thicket of swarming scooters, then YES driving is more difficult than in NYC. Parking is not necessarily MORE difficult, and perhaps not AS expensive.

Driving into and out of any of these three cities is quite do-able. But your van will almost certainly not be useful to you to move about the city, at least not to touristically important places.

Best wishes,

Rex

yes - MUCH. NYC is laid out on a grid so though traffic is slow, at least it is semi-organized. Driving in these cities is just as congested as NYC, but there is the added problem of extremely narrow streets laid out hundreds of years ago. Plus trying to drive while confronted by signs in Italian or French. Hard if you are fluent - terrible if not.