when I still had access to flat rate seats at work (I think equivalent to the consumer 200/mo) I was at estimated ~8000-ish/month api costs at 100% usage, which is 400/workday. This with maxing out the 50% fable usage and using opus for the rest, usually 1-3 concurrent sessions.

Having moved to api billing (where my spend is not allowed to be nowhere near that high), I think that estimate was conservative and I wouldn't be surprised if it was more like 500/workday equivalent.

I am glad I was able to do a lot of experimenting and learning while we were on flat rate, and I am surprised a lot of coworkers did not take advantage while they could.