The General answer would be yes, you are at a disadvantage.
But depending on what area of Brooklyn, you may not be because there are still too many listing agents that just will not co-broke. They would rather keep the whole commission to themselves, even at the expense of their seller not getting the best price.
But also, unfortunately there are too many buyers agents that are just riding along on the coat tails of a buyer and have no idea what they are doing. They are not helping you the buyer to formulate your qualified best offer, they are not helping you even find the right properties that you are qualified to submit offers on. And remember it is not just people that have to qualify for a mortgage, houses do as well, some properties may not qualify for what you are working with and the sellers broker should know that, so cannot accept your offer.
Also if you are working full time, you will not have time to watch for the new listings and also keep up with the real market. Your buyers agent should be a full time agent that specializes in the area that you want to buy in, that knows every house in the neighborhood, knows all the agents in the neighborhood and that can do a complete records search for you as well as an "inspection" of the condition etc. as you are going through the property, so that you can make a solid offer quickly. Then they can help you structure and present your best offer and hopefully get it to a closing.
I have represented many buyers recently that have been looking on their own for, in some cases many years and the market just kept running ahead of them and they spent 1,000's on home inspectors just to have to withdraw their offer because the property needed too much work etc. they did not know which Bank or what financing was available for what they were trying to buy, or their offers were not presented in a fashion that a sellers Broker could accept, but the sellers agent did not have the time with all the other offers they were getting to get the offer where it could have been accepted.
Working with a good buyers agent is like having your own personal Coach, working with a bad one is like pulling a huge weight along with you.
A good buyers agent will not always tell you what you want to hear, they should give you options of what is possible to get to your end goal.