FYI, Azure already has monthly spending limits built in and suspends your account once you hit the cap. When you go over your limit your compute services are a

FYI, Azure already has monthly spending limits built in and suspends your account once you hit the cap. When you go over your limit your compute services are all turned off and your data is rendered inaccessible until your account is resumed (which happens at the end of the month or when you raise your spending limit). (Full Disclosure: I work for the Azure Web Apps team)