"The owner has purchased a larger boat for long-term cruising."

That's going to attract bottom feeders. I realize that's the broker's strategy -- but other prospects are going to be prompted to low-ball if they have that info in mind. Unless you're really ready to accept a low-ball sale you don't want buyers to know you've bought the next boat and you've already moved on. Might as well say "bankruptcy sale" or "estate sale". Same effect.