This is especially easy if you can shutdown environments that are only used for dev/staging tasks. With 168 hours in a week - how many hours do those things need to be running?
I run a little tool for Heroku to make it easy to do this kinda thing.
Often the continous use discounts make regularly turning on and off a wash.
This assumes they have something like RI etc for those resources. Those are typically used for production, but far too often, dev/test resources are usually turned on ad hoc.