I have an order form on my website that basically gives the users access to a specific part of the website. So no shipping is required. All that's needed is they select which items they want (website sections) and then have them send the money to my paypal account. Upon doing so, my website would receive notification (return URL?) and can them add them to the database.
I've looked into the Express Checkout solution but that seems to be a bit more than what I need. Mainly because it requires shipping info.
What other options does paypal have to accomplish what I need?
Also, how would I go about authenticating the completed purchase? For example: Paypal allows me to set a return URL once purchases are complete. So on that page, I could add the user to the database. However, what is there to stop people from manually loading that page and getting added to the database without paying for anything?
Does paypal provide authentication for this? Do I need to handle this myself? If so, I was thinking of appending a nonce to the return URL and checking that against the user when the return page loads. Would this suffice? Are there better alternatives?
It sounds like you may NOT be a coder. In order to get full access to all of the features, you will need to write an application to integrate with PHP.
On the other hand, you could simply use the PayPal shopping cart. They manage virtually everything on their side. You just add a "paypal shopping cart" button to the pages you want and when the user clicks it, it will add the product to the shopping cart. You of course have to identify the product for each button, but it is really simple to use. You can see the reference here: