If you are making a reservation or sending a quote to prospective renter directly from Wheelbase, you can change their 'locale' which tells the system to send that renter the system's pre-made emails in the corresponding language. (Note: any customized text you've added to emails won't be translated, what's changed is the system created emails that we've recreated in numerous languages).
Suppose you have a renter contacting you from France
Create the quote as usual
Below the renter's phone number, select the language/country from the "Locale" drop down
If a renter books directly from your website:
They will be able to select their locale, which will update the currency and the language they'll see throughout the booking process and confirmation emails sent by the system.