The traditional selling technique of getting to "Yes" at all costs is flawed.
"Yes" is often a meaningless answer that hides objections, pushing hard for "yes" doesn't get you closer to a win, it just angers the other side even more.
"No" is not a dead end. For good negotiators, "No" gives you an opportunity for the negotiating parties to clarify what everyone wants by eliminating what they don't want. "No" will always alters the conversation and pushes the negotiation forward.
Go for the No.