The budget cost of opening a smaller grain and oil store is about 654.38+10,000 yuan to 300,000 yuan. Investment will also be affected by geographical location, rent, decoration costs, equipment purchase, personnel costs, raw material procurement and other factors.

When considering opening a grain and oil store, we should comprehensively consider the above factors and formulate a detailed business plan and budget to ensure the feasibility and profitability of the investment.