1. Most Hotels ( 3 star and 4 star ) will not need ID upon checkin but will need a Credit Card.
2. Once you give your credit card, they will call the company and ensure that you do have enough funds for a one night stay + about $25 to cover any extras ( telephone, Minibar...)
3. They will ask the CC company to block the amount ( 1 night + $25 approx. ) and they will get a confirmation # from the credit card company.
Most people do not know this but As I work in one of the Hotels Downtown, I can Tell you that this is the Procedure to follow.
If you show up at Check-in with the SP, some hotels might ask for BOTH ID ( specially the hotels that do not encourage SP services )
Frenchy