The rare resource strategy requires you to examine the board to see which resource will be the hardest to get throughout the game. One should consider putting one of their settlements on the best tile for that specific resource. Having that supply of the rare resource will become more valuable throughout the game and you can trade that resource for whatever you need.
This strategy is all about identifying the rarest resource and making sure that you have access it. There are two ways that a resource can become rare in a game, one in that bad numbers are placed on the resource/bad production, and second in that rare availability. Rare availability may occur because ore and bricks are the only two resources with fewer than four tiles in a regular game. This event makes having a direct contact with either of those two resources significantly more valuable. Most of the time though both of these situations will occur, which increases the value of having a settlement connected to that particular resource.
This strategy isn’t about monopolizing on the resource, but rather you want to share the tile with at least one other person to reduce the risk of being hit by the robber. You just want make sure that you have access to that resource. The only way that using the rare resource strategy works is if it is used along with another strategy. The key of this strategy is to just make sure that you have access to the particular resource, which will be in high demand.
The downside if you don’t use this strategy is that when the game gets going you will need to have these rare resources to continue expanding, building cities, or getting development cards.

