Website with payment gateway

Website brief:
Industry: Communications, Interpreting
1 landing page for Clients with brief info on how it works and link to booking portal (separate service, already purchased via another company, NOT part of the brief, you will not work to develop the booking portal as it is a separate system which will be linked via API).
- page for Interpreters with information on how it works and link to portal where they would register their details (same as above, you will not be working on the portal).
- secure payment gateway (PayPal a plus) but should allow bank transfer etc. with Invoice reference.
- page on specific service options and discount notifications or links (the principle is we want to post here our recommendations from us to help clients make informed choices).
What is important: website design should be very modern and fluid, easy to read and navigate. Payment should be easily accessible.
APP as further dev project is an option, provided this website is successful.