Directly, and early. Concerns exist before the investment is ever shown — they form from past experiences, things they've heard, and people they've talked to. Asking about them in discovery isn't pessimism; it's scheduling. The same concern takes a question at minute twenty and the whole close at minute ninety.
The short answer
The documented posture is invitation: find out what they've heard, find out who else they've talked to, ask what they're comparing, and ask what could make them hesitate. None of those questions plants a concern — the concerns are already planted; you're asking where. And a critical distinction keeps the conversation calm: concerns are not automatically objections. A concern is information looking for an answer; it only hardens into an objection when it meets surprise, defensiveness, or a number.
How it runs
A concern surfaced in discovery gets answered inside the presentation, as proof placed where it belongs — the warranty section answers the labor-coverage scar; the company story answers the disappearing-contractor scar. That is a completely different experience for the homeowner than raising the concern at the close and watching the rep improvise. It also changes the close itself: with the concern layer already mapped, the objection that does arrive is usually the real one, and the framework can do its work on a single, honest target.
Spar grades your probing against the documented system, round by round. Round 1 is free. Spar before you knock.