Can I take a Taxi (4 adults + bags) from Shanghai Pudong to Suzhou ? And how much it .

The taxi can be found, but few taxis want to go to Suzhou due to the long distance between the two places.
If by taxi, the taxi fare is about CNY 500.
And according to your situation, maybe you need two taxies.
So you can take long-distance bus at the airport. There are lots of schedules every day. And it will take around 3 hours on the way. It's also a convenient way for you to choose.