IMHO, not much.
Firstly, when you approach a broker, they are going to try and show you the boats they have listed. Don't kid yourself, their fiduciary responsibility at this point is to the seller, not the buyer.
Once they can't find a boat in their listings, then they slide the 'buyer's broker' contract over to you and hit Yachtworld. This entitles them to split the commission 50/50 with the listing broker.
The commission comes off of the sellers end, so insinuating that the buyer is paying is silly. The buyer wouldn't get a 10% discount for a private sale. That golden ring shines in the eye of the seller.
You can find the same boat on yachtworld and approach the listing broker. There is no magic, hidden MLS listing for boats that only brokers have access too.
FWIW, I completely agree. Your comments reflect my experiences.
I'd guess the potential value of a 'buyer's broker' will depend completely on the individual. During my extensive, protracted, and many searches for used boats, I would have loved to have benefitted from a buyer's broker.
Many, many brokers approached me, offering to act as a 'buyer's broker.' I tried working with several over the years. My experiences were as you described. I would get dumps of listings from yachtworld (that I already knew about), I assumed so that the broker could claim they introduced those boats to me and thus qualify for a share of the commission.
Some claimed they had access to boats before they were listed on yachtworld. I never saw that. Occasionally someone would send me a listing just as it was appearing on yachtworld. But I saw no evidence of a 'secret world' of boats for sale that didn't also hit yachtworld. It's in a seller's interests to reach as wide of an audience of buyers as possible, to maximize the selling price. It would seem most sellers would have little incentive to do a private side deal.
Most of the 'buyer's brokers' tried to talk me into buying boats. Which is understandable, since they only get paid upon a sale. But it wasn't helpful to me. Exceptions to that behavior were rare. One broker I dealt with was above board and principled, and didn't try to talk me into anything (probably because he knew in the recent hot sellers market, another buyer would come along in 5 minutes if I didn't buy). One other broker was the only one I dealt with who actually talked me out of buying some boats, candidly telling me they weren't worth the price and had too many issues. I have great respect for him. Even though he didn't bring me any unique listings, I sensed he would have been helpful in actual negotiations, and I would seek him out to work with in future dealings.
The point made by Shrew is an important one to remember. The broker's fee comes from the seller, and if the broker owes anyone agent-like fiduciary duties, it is the seller. Before you take the 'buyer's agent' into your confidence in the course of a negotiation, you might want to consider that.
You might get lucky. The broker you choose might be aware of a likely boat that is not public knowledge (although, like Steve K, I rather doubt that). They may genuinely want to steer you away from problem boats- although that was not my experience. I made an offer on a boat from 'my' broker's branch agency, and walked away after survey. I ate those costs, and did a private deal for a different boat. The purchase price reflected the lack of commission and my legal fees were a small fraction of half the usual commission.
It's true that while the fee to any broker is technically paid by the seller, as others have pointed out, the money actually comes from the buyer. As others have said, the only source of money in any boat sale comes from the buyer. The seller might be the one disbursing the funds, but the money comes from the buyer's wallet.
FWIW, I had thought that working on my own, without a buyer's broker, might provide some flexibility on price. After all, if a selling broker doesn't have to share the commission with someone, it stands to reason they should be more flexible and willing to partially reduce their own commission to help make a deal happen. That would be a win all around - a deal happens so the seller gets their boat sold, the buyer pays a bit lower price, and the selling broker ends up with a higher commission than if they had to split it 50/50.
I've experienced that in the past, but was surprised that over the past three years, no selling broker I encountered was willing to reduce their commission at all. It seemed to be they both saw it as an extra bonus, to keep the full commission for themselves, as well as probably knowing that in a hot seller's market, someone else would come along willing to pay the full freight.
