The grain markets occupy an imperative position in the economy of Northern Ghana. As places where retailers and consumers meet, they bring together the forces of supply and demand to determine price. Information on price variation and its effects on consumers in the retail trade are required to make effective decisions. An effective and efficient grain marketing and pricing system would help keep the markets in balance considering the variation of prices and sometimes quantities for a homogenous product from retailer-to-retailer for equal measures within and between markets. This problem leads to higher than expected food cost to households who become dissatisfied with the performance of grain retailing in markets. In providing a sustained analysis and research into price variation, pricing system, grading and standardization are likely to thrive in the food retailing trade in Ghana and other developing countries. How can one determine the causes and effects of price variations in retail trade for maize and rice? This work explores this in detail, and provides recommendation to address this problem. The methods used and the results obtained will help solve grain retail problems.