How does PayPal checkout work?
PayPal Checkout, explained
Instead, on sites with PayPal Checkout enabled, they can simply log in with their PayPal username and password, select the payment method already connected to their PayPal account, and that's it — purchase completed.
Why is my PayPal Pay in 4 not working?
The purchase is not within limits
PayPal Pay in 4 services is only available for items between $30 and $1,500. If our order is below or above these limits, we will not be able to choose to use this payment method.