You'd better get the contact lenses at the real optical store. The optometrist will give you an eye exam, so your contacts are made based on your own prescription.You should buy reputable ones with the good quality, becsuse the contact lenses touch your eyes directly. The contacts cost usually depends on your contact lens prescription, the type of contacts , where to buy them, and so on. Personally think If you are nearsighted and are prescribed a popular brand of disposable soft contact lenses, these lenses usually are sold at a retail price of $22 to $26 for a box of six lenses. You can also shop around by yourself to know the exact information.