blind quote
A blind quote is an estimate of the cost or service when no, or limited research is done to pin point a more accurate amount or timeline. This is less through than a standard estimate where time is available and given to narrow down a more likely cost or timeframe.
I pushed the guy at the repair shop to tell me some amount for my brake repair. He gave me a blind quote, but said this is his best guess without seeing it, and thus not official.