When making a reservation online, you are required to provide a valid credit card as a form of guarantee.  It will not be charged immediately.  When and if the card held as a guarantee will be charged varies by hotel as noted below.

HOTELINDIVIDUAL HOTEL DEPOSIT POLICY
Best Western Atlantic Beach

Four Points Miami Beach

Holiday Inn Miami Beach Oceanfront

Lexington Hotel Miami Beach
A deposit of one night’s room and tax will be charged to your credit card on or after December 25, 2018. 
AC Hotel Miami Beach

Cadillac Hotel & Beach Club

Circa 39 Miami Beach

Confidante Miami Beach

Eden Roc Miami Beach

Fontainebleau Miami Beach

Grand Beach

Hilton Garden Inn Miami South Beach

The Palms Hotel & Spa
Your credit card will be held as a form of guarantee only and not charged an advance deposit.  The card will only be charged if the reservation cancels with the Hotel’s cancellation policy or if the reservation no-shows.