You can add as many addresses as you like to your customer contact. You can do this while you are in the process of creating a new customer or going to the customer database to edit an existing customer's information.
Click the 'address' tab in your customer's information form. Below the first address, you will see a blue '+ new address' button.
Once you have clicked the '+ new address' button, a new address field will populate for you to fill in. You may add as many addresses to a customer as you need, by repeating the previous steps.
Make sure to select the address that will be used as the billing address by clicking on the '$' icon on the right hand side of the addresses. The icon will turn blue once you've selected the billing address.
You also have the option to delete an address by clicking the 'X' directly above the '$' icon on the right hand side.
After you have finished entering the new address(es), simply click on the blue 'update' button on the bottom right corner to save.