Client side photo site

Hi im a professional photographer and ive created a website. what i need is an area for clients to log in each company with there own username and password and be able to download photos. each company can download more than one photo but after a photo is downloaded by one compamy it cant be downloaded by another so the image will be removed off the server. also? ide liked to be emailed when a photo is downloaded and by which user it was downloded by.