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AIBuildCounts
AIBuildCounts specifies how many building of this kind would be built by AI. Often used with Limit=x command. Through AIBuildCounts AI actually can override Limit= and build more of a kind.
3 numbers correspond with difficulties: AIBuildCounts=3,2,1 means Hard AI would build 3 bbuildings, Medium 2, Easy 1. You're not forced to use maximum numbers, better specify oprimal count and let AI have additional with help of AIExtraCounts.