Every payment accepted within the Guest solution is associated to an Order. This can be thought of as a container or 'cart' for all products, tangible and physical, that are part a single purchase. Multiple payment types for a single order are not supported. Only a single credit card may be used for the entirety of the order.
Stripe is a 3rd party API that allows the Guest solution to tokenize, and process consumer credit cards.
All uses of the SDK or API with a Sandbox API Key, will be creating dummy transactions, that will not actually be processed by a bank. Stripe makes a very clear distinction between dummy/test charges and actual production charges. This allows developers to test end to end cases, without incurring actual costs on a real credit card.
Stripe allows for the pre-authorization of a purchase, which will guarantee the funds on the payment card for up to seven days. This will happen in the solution while a booking is being confirmed by the supplier. See the Stripe documentation for more details.
The Guest app employs several booking strategies, such as bookable, parking, accommodation and transportation. You can find more information about it here.