Basecamp team started by looking at the legacy apps and comparing real traffic to their forecasts. It turned out that by re-planning their spent , and taking advantage of AWS prepaid instances, they were able to save 250k out of $500k they were putting into legacy systems. After that, they wrote some tools to display what they were spending and where, and the team looked for sudden increases. Lots of charges were not obvious, and they had to go through AWS documentation’s and pricing charts to figure out what each line item was for. It was very time consuming, but at the end, Blake and team were able to save ~20% of their cloud storage bill.