There are 2 ways to shop. First, you can choose a personal shopper. You pick out specific items you would like and then your personal shopper purchases them for you and ships them directly to you.
Second, you can sign up for their package forwarding service. You purchase items yourself and have them shipped to UsGoBuy's warehouse. Once you've purchased everything you want and it all arrives at the warehouse, UsGoBuy ships it off to you!
You can take a look at USGoBuy's fees and terms here. And they offer personal shopping and shipping for more retailers than just cosmetics. You can check them all out here.
UsGoBuy is running a special promotion for new customers until Thanksgiving: up to $65 off shipping rates on your first order! Find out more here.
Disclaimer: I was compensated for this post, but all opinions are my own.