Q. If I have an Azure enterprise agreement can I use quotas for different groups in my organization?
A. At time of writing a quota can be configured at a departmental level (and under departments there are accounts which contain subscriptions). When defining quotas at a departmental level you define the quota and also alerting options to enable notification at certain thresholds such as 50%, 80% and so on. There are billing APIs also which could be used with your own script that could check current spend at levels such as accounts and subscriptions, compare to values you configure and perform your own custom alerting however this would all need to be custom written. There is a third-party solution called Cloud Cruiser which brings a rich insight and tracking to Azure spend at numerous levels which makes this a good option if you need detailed insight of spend in Azure.