I would like to have the best place to buy a Samsung galaxy S4 international unlocked cell phone. I want the cheapest price I can get.
Depending on the country you live in you should be able to search for a price comparison site which will or should guide you to the cheapest store locally.
You will get the lowest price on eBay but the phone will come with 1 year dealer's warranty instead of manufacturer's warranty, which means if ever something goes wrong with your phone, the service center wouldn't cater to it for free even within one year, instead you'll have to post your device to the dealer whom you bought from.
Search on Online Shopping Site, you will get good options and you can compare prices also.