Estimate is related to Price. Price is related to Due. Due is related to Monthly. Monthly is related to Payment. 
Gross is a type of Sum. Sum is related to Column. Column is related to Sculpture. Sculpture is related to Statue. 
Estimate <--RelatedTo--> Price <--RelatedTo--> Due <--RelatedTo--> Monthly <--RelatedTo--> Payment 
Gross --IsA--> Sum <--RelatedTo--> Column <--RelatedTo--> Sculpture <--RelatedTo--> Statue 