A GPU job should end with a receipt
Quote the job. Watch it. Settle it.
Quote first
You see the files and the locked provider rate before a machine exists. Confirm spend, or let an agent set confirm_spend after that quote is accepted.
If the machine never becomes ready, the charge is $0. No subscription. No leftover box.
Meter the machine
Provider rate, passed through, billed by the started minute. Plus a simple fee. A $100 run is $107.50. Prepaid, $10 minimum.
When the function returns, the machine is torn down and you get a receipt.