Sometimes buyers have special requests, so you need to collect additional money from them but you don't know how.  The absolute easiest way is to create a payable invoice in seconds.  Here's how to do it:

You will need to have a Pay Pal account BUT your buyer does NOT need to have PayPal! PayPal is AMAZING for invoices because the buyer can use ANY credit card, debit or even a check! PayPal is accepted by ALL of the world except for Central African Republic, Christmas Island, Equatorial Guinea, Haiti, Heard Island and Mcdonald Islands, Iran, Iraq, North Korea, Lao, Lebanon, Liberia, Libya, Myanmar, Nigeria, Pakistan, Papua New Guinea, Serbia and Montenegro, Sudan, Syria, Turkey, Zimbabwe. So there is really no reason your buyer can’t use it. 

Now that you realize how awesome PayPal invoices are, here's how to create one.  

Login to your PayPal account and click "Pay & Get Paid" on the top row:

Next, click "Create & Manage Invoices":

Then click the "+ Create Invoice" icon:

Then simply fill out the form:

SUPER IMPORTANT TIPS:

The "Terms" section at the bottom of the invoice is something you ALWAYS want to fill out:

This is what you want the Terms to include:

• When payment is due by?
• If buyer does not pay by that date, is the order canceled?  
• Is merchandise returnable?  If so, how long does buyer have to return it?  Can it be returned used?
• If merchandise is returned, is there any restocking fee?
• When will merchandise ship?
• Is there anything the buyer needs to do?  For example, will the parcel require signature?  Will the parcel be held at the buyers local USPS for pickup?  
• Is insurance included or did buyer state they do not want insurance?  If buyer does not want insurance, what happens if the parcel is damaged, lost or stolen?

If it is being sent internationally, you need to add to your Terms:

• "Buyer is responsible for all Taxes / Duties / Vat or other charges associated with importing merchandise into his / her country."
• "Buyer is responsible for taking whatever actions are needed to get the parcel from Customs.  This may include paying taxes, filling out paperwork, picking up from Customs, or other"
• "Buyer is responsible for only importing merchandise that is allowed to be imported into his/her country.  (Your company name) is not responsible for merchandise seized, taken or destroyed by Customs due to illegal imports"
• Parcel may take several days or weeks to clear Customs.