I will list the general rule but, it all depends on how full you would like your hair and the length you desire. 10" - 22" 3 Bundles 22" - 26" 4 Bundles 28" & up 5 Bundles When purchasing lengths 24" and longer double your longest length so that you have a full bottom. For example, purchase (2) 26" (1) 24" and (1) 22". (Closures do not substitute for a bundle, you will still need the same amount of bundles.)
With good care extensions will last 1-2 years. If the hair has been chemically altered (such as bleach and dye) it can still last up to a year. Lace closures usually last between 2-3 months. Because of the unique and delicate craftsmanship, lace frontals have a shorter life span of 4-6 weeks or 1-2 uses, and typically need to be re-applied and strictly maintained in order to get the full wear.