You cannot send the invoice to your own email address, that won't work. In order to accept credit cards on the the spot, you would need to use PayPal's Virtual Terminal.
If you have an laptop and an internet connection, PayPal's Virtual Terminal or VT on site would work. There is also an 3rd party card reader available for VT called USBSwiper and PayPal offers a product called VT Swipe. If that's not doable, then Virtual Terminal could be used at home to process the transactions later after the show. Note, you would need a manual imprinter to collect the customer info and you then process the transactions later. This is proof of accepting someone's credit card because you now have an impression of the card on the receipt. For some credit card companies, this is "required" information should you have a chargeback situation. VT costs $30 a month, sale or no sale, plus the transaction fees. But beware, processing the transactions later is risky. Someone could purchase an item, give you a bad credit card and you would not know about it until after the fact. Then it's too late.
Note, Virtual Terminal is needed because you cannot simply use your regular PayPal Account to process the transactions. Here's why. Your PayPal Account is only setup for you to use in a specific way. If you would try to use it to process purchases yourself, it will cause issues. PayPal looks at the IP Address of the computer and Mac Address of the your network adapter. Lets say that you have ten transactions, all using different credit cards. PayPal will see that unique IP Address and/or Mac Address and note that each time a different credit card has been used to pay for a transaction. Because of PayPal's Fraud Security, this activity will appear suspicious. It will be viewed as some sort fraud attempt which in turn will set off some red flags. And there's a good chance that your Account will be frozen and/or locked. This is by design.
On a personal note, you may want to look into a separate Merchant Account and a wireless card processor. Over the years we have tried various methods for processing credit card transactions on site. We do a lot of shows and outdoor events. Most methods we tried were slow and/or cumbersome. Customers want and expect paying by credit card to be a simple solution and fast, they don't to wait. Our solution was a separate Merchant Account with our local bank and we use a wireless credit card machine. This system allows us instant transaction authorization on site. No more hoping that every card is valid when you go home to do your batch processing in the evening. It only takes one bad credit card to ruin your event.
Check out some of your local banks and see what they offer in the line of Merchant Accounts. Then compare the costs, service and support they offer. We do use PayPal for processing transactions on our web site however, for transactions in person, we use our separate Merchant Account and our wireless credit card machine. This system is easier to use than Virtual Terminal, costs slightly less per month and the support our bank provides is great.
Regards,
skier
