At this time, it's not possible to allow both payment options (Take Credit Card Details and Paypal) with the BookNow app. You must choose one option (either take the credit card details which does not charge their card, or take Paypal, which is a confirmed payment). With the Paypal option, you can also elect any percentage amount (up to 100%) as the deposit/non-refundable portion of the booking.
Even with this limitation, it's important to realize that Paypal allows customers to pay with a credit card, even without having a PayPal account. In other words, you can choose the Paypal option, which will give you the flexibility of customers paying directly from their PayPal accounts, and it will also allow customers to perform a one-time payment with their regular credit card.
If your customer base lives in a location where PayPal is not permitted or accessible (even for one-time payments) then you may want to choose the option of "Take Credit Card Details).