Worth buying a Yacht?
From Fallen London Wiki
The Fruits of the Zee Yacht is a clear winner here, but even without that it seems to be worth trading up.
If you try for a Yacht, four failures and a success (slightly more than the expected number) will cost you 377.5 Echoes. Swapping the base choice to the Yacht choice saves 687.5 Echoes, so you can afford far more failures than average and still turn a profit.
If you're set on the Clipper or Zubmarine, or have another FotZ option already, this may change - you'll have to invest in swapping back too. But anyone who settled for the Tramp Steamer has a chance to save Echoes while upgrading their ship.