Arrival : Best of 10 days (Venice, Florence & Rome)

I believe both hotels are identical. Venice street addresses can be maddeningly difficult for outsiders to understand. Napoleon came up with the system.
The Hotel La Fenice et des Artistes is across the street from the north side of La Fenice Opera House. It is located in the center of the island, not totally convenient to public transport docks. The Giglio stop is probably easiest. A water taxi (cost is total for both of you) can get you within about 50 feet of the hotel, and the taxi driver will probably know exactly where it is. The opera house is a very famous Venice landmark.
There is a water taxi desk in the airport where you exit the secure area with your luggage. They will direct you to the dock, which is about a 600 yard walk from the airport doors.
For in between price, you can do a shared water taxi. Cost will be about half, but you may be the last ones to get off the boat, depending on where the other ride-shares are going. Again, they can get that organized at the water taxi desk.
Here is the website for the water taxi co-operative, including prices, ride share, and airport arrival. http://www.motoscafivenezia.it/eng/

Thanks -
After my post I found that other option - shared ride. here's that link: http://venicelink.com/.

Though one negative is that it seems you may have to wait from 20 - 40 minutes to see if others could use the same boat.

The boat carries I think up to 5 people.

So the taxi may be the best option.