To most cost-efficiently buy a home with a mortgage, prioritize improving your credit score, shop extensively for mortgage rates, and strategically structure your down payment. A higher credit score (ideally 740+) secures lower interest rates, reducing lifetime borrowing costs. Next, compare offers from multiple lenders using tools like those from LendingTree or Bankrate to identify the lowest rates and fees. Finally, aim for a 20% down payment to avoid private mortgage insurance (PMI) and consider loan types like a 15-year fixed-rate mortgage, which offers lower rates but higher monthly payments.

The key factors are credit score, mortgage shopping, and down payment strategy. A FICO score above 740 typically qualifies for the best rates, with a 20-point increase potentially lowering rates by 0.25% (myFICO, 2023). Mortgage rate shopping can save up to 0.5% on average, translating to $50 monthly savings on a $300,000 loan (LendingTree, 2023). A 20% down payment eliminates PMI, which costs $100-$300 monthly on a $500,000 loan (Fannie Mae, 2022). Negotiating closing costs with lenders or using a loan estimate comparison can save $5,000 on a $300,000 home (National Association of Realtors, 2023). These steps collectively reduce interest payments and upfront costs, maximizing affordability. For example, a buyer with a 740+ score, 20% down, and a 3.5% rate on a 30-year loan at $300,000 saves $240,000 in interest compared to a 5% rate (Bankrate, 2023). Strategic planning ensures long-term financial efficiency.