You will not be charged anything until your trial expires. We don't even ask you to enter a credit card to get started.
Never! You simply pay month-by-month, and you can cancel any time.
There are no limits at all during the 14 day trial. It's a fully functional account, with unlimited everything.
You can put your credit card information into FlexBooker at any time during your 14 day trial. But don't worry, we won't ever charge it until the end of the trial.