Yes, a day. When you're dealing with a bug that could disrupt all international transfers at your bank for several days, and the kid you have on staff who learned RPG on YT has reached his limit, it's cheap.
I learned about it from a friend who worked at an IBM partner with a tool to help translate RPG to something else. Rarely worked because of the decades of nuanced patches to deal with evolving business rules, and when it did they usually came in several million above budget.
Do you actually mean 100-500k per day?