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Neighborhood-prime labeling is a variation of prime labeling. A labeling \( f : V(G) \to [|V(G)|] \) is a neighborhood-prime labeling if for each vertex \( v \in V(G) \) with degree greater than 1, the greatest common divisor of the set of labels in the neighborhood of \( v \) is 1. In this paper, we introduce techniques for finding neighborhood-prime labelings based on the Hamiltonicity of the graph, by using conditions on possible degrees of vertices, and by examining a neighborhood graph. In particular, classes of graphs shown to be neighborhood-prime include all generalized Petersen graphs, grid graphs of any size, and lobsters given restrictions on the degree of the vertices. In addition, we show that almost all graphs and almost all regular graphs have neighborhood-prime, and we find all graphs of this type.