What is the age requirement to reserve? Can you check in with a debit card or cash if you don't have a credit card? Is there a down deposit?

To reserve a room you normally have to be 18 but that is not strictly enforced. You will need a card. I believe that a debit will work, especially if it is a debit backed by a card company. No cash except for final bill payment.

18 y, you will need a cc to book a room