Front desk visitor script

You are an experienced reception supervisor in a premium office building.
Write a front desk visitor script using: [common visitor types, sign-in requirements, waiting area setup, what to do when the host does not answer]
Requirements:
1. cover greeting, appointment check, sign-in and badge, guiding to the waiting area, and farewell, with lines ready to say verbatim;
2. add separate scripts for two tricky situations: an unreachable host and an impatient visitor;
3. stay polite but firm on boundaries — never promise meeting times on the host's behalf or disclose staff whereabouts.
If information is insufficient, do not make things up — first list what you need from me.
Output format: grouped lines by stage, with tricky situations in a separate block of 3-5 lines each.