We were told by friends we must approach Venice from the water and pre-paid (£95) a water taxi for four of us to travel from the airport to Venice.
Two days before leaving we received our documentation from Octopus travel which said the transfer would usually be by water taxi from the airport but the taxi firm could alter this to a car transfer to P Roma and water taxi from there to hotel.
We raised this with our travel agent who checked and said they thought the car transfer would only be in exceptional circumstances, but they were sure we would be transferred by water taxi all the way. It was too late to make alternative arrangements and we let it be.
On arrival, sure enough, we were told ther was a car waiting for us to take us to P Roma. We said this was unacceptable, but despite prolonged arguments with the agent and their head office by phone, they refused to put us on a water taxi at the airport. They told us they no longer did water taxi transfers from the airport as the walk to the taxi terminal was too long (800m), and also it might rain. So despite us booking and paying for a water taxi transfer from the airport, and receiving a confirmation that this would normally be provided, there was never any prospect of this happening.
We were then transferred in a glorified van to P Roma, had a 10 min water taxi ride on the back canal, and were then dumped some distance from our hotel and we had to walk at least 800m to the hotel!
Our return to the airport was arranged by the hotel - water taxi arrived on time at back entrance of hotel and transferred to airport. Walk to terminal building perfectly easy - under covered walkway in event of rain - cost £66 instead of the £95 we were conned out of by pre-booking.
DON'T PRE BOOK WATER TAXIS- LOADS AT AIRPORT, MUCH CHEAPER AND YOU GET WHAT YOU PAY FOR!