How long does homemade tomato sauce last in a jar and what are the best storage practices to ensure its longevity?

Homemade tomato sauce can last in a jar for about 5-7 days in the refrigerator. To ensure its longevity, it's best to store the jar in the refrigerator immediately after making the sauce, ensure the jar is tightly sealed, and avoid cross-contamination by using clean utensils when serving the sauce.