What to ask, and why

How do I make sure treatment is done before the photographer shows up?
Have it scheduled backward from your photo and listing dates, with ventilation time built in. Share those dates on the first call.
What if buyers still smell it at the first showing?
Odor that returns usually means a source was missed or new odor built up. Ask what was treated and what conditions, like a damp crawl space, could bring it back.
Is chlorine dioxide safe to use in a home I'm selling?
It's used in a vacant space under controlled conditions, then ventilated before anyone returns. Ask for preparation, dwell time, and re-entry details before scheduling.
How do I avoid surprise charges?
Get a written quote before anything starts, and ask to be told before anything new, like carpet pad that has to go, is added.
Can my agent handle access?
Often, yes. Many treatments are coordinated directly with listing agents.