basically doing cold calling using vapi voice model, gemini-2.0-flash, deepgram the estimates my client gave is that he'd be doing 10,000 calls a month. Idk if I believe that number but im curious about what 1000 calls, 5000 calls, and 10000 calls / month would look like. Also, curious what a "failed" call looks like - meaning when they don't answer, goes to voicemail, or silence after calling. Thanks!