Need help with e-commerce site

A person is asking me how much it will cost to build an e-commerce site for him, I design sites myself but have never done an e-commerce site so I need someone to handle the ecommerce parts of the site or we work together under the client's direction, he knows what he wants. He wants the site to mirror this one: [login to view URL] he wants to upload up to 100 products with paypal payment method, shopping cart and checkout. Also a youtube video and links to his facebook and twitter. He will also want his company name in some sort of stylish text as he does not have a banner. He wants someone who has built a similar e-commerce site before and will only choose someone who can send me a link to past work done as in that site, what you will charge for us to build that site and how long it will take. Please note that he has not given me the job, he is asking what it cost. If we can work together to get this site done at a good price I will then start seeking out other ecommerce jobs for us, thanks.