Anyone with experience booking guided tours that leave directly from either the Hilton Molino Stuckey, or the Boscolo Venezia?
None ypu would need to book a private tour all shared tours meet in various parts of the city.
Save yourself some money. Buy a good Venice guide book. I like the Michelin Green Guide to Venice together with the guide books published by Knopf, DK and Time Out. these have good street map in the guide books. Read one or more of these books well in advance of your visit and decide what interest you most rather than what the tour guide decides to take you to.