You can use several payment methods to pay for your monthly subscription fee. We would accept any of the major credit/debit card brands, and PayPal.
Here are the accepted payment methods by Smartbnb towards your subscription:
Visa (all currencies)
MasterCard (all currencies)
AMEX/AmericanExpress (in all currencies, but not SGD)
Discover (in EUR, USD).
PayPal (all currencies)
PayPal would require to setup a backup payment method (a card or a bank account), but PayPal will always try to fund your subscription payments from your PayPal balance first.