custom price for whislist products, email prices

Ability to add a custom prices for people who have product son their wishlist, this should be arranged per customer, if customer x wants product y, after few days we reduce the price of product y for customer x, but if customer z adds product y to wish lsit, this should not affect the price, like we give a new price for customer z for the same product. Also instant email the special prices when special wishlist prices are given. Have validity period also maybe?