Boats priced in your range, with a
broker fee of 10% split twice (listing and selling) then split 60/40 (60% to the central office and the rest to the broker), doesn't leave the
broker with much incentive. Granted the paperwork's no more than a hour or so, and you do have to coordinate things, but it probably isn't worth the brokers effort.
You're not alone in this problem. Unless you agree to the asking
price getting any broker to
work with you isn't going to happen with any regularity. Here in
Florida, brokers are required by law to present all offers to the seller. Whether the broker calls you back or wants to spend time haggling, isn't a law.
If you're dealing with the listing broker and getting that lack of
service, unless you've got your own broker (and having one can pay for itself quickly) and s/he's willing to hound the other broker, things are going to go real slow.
As others have suggested, it's time to walk the docks,
cruise the
boat yards, and look behind folks houses for
FOR SALE signs.