Add up what the brokerage pays every month for software and per-closing fees, then divide by production. Defaults are editable examples — enter your own stack.
Nowhere — they are plain editable examples. Pull your real invoices and your closing count, and the percentages do the rest.
Only if the brokerage pays them. This is the brokerage’s stack view — keep agent-paid tools out or run it twice, once per perspective.
There is no honest universal number — it depends on your GCI per closing. The useful move is tracking it over time and asking, at each renewal, what this line bought.