There's no single interview question that tells you whether someone can sell.
I've been asked this hundreds of times. "What's the one question I should ask?" The honest answer is that it doesn't exist. Whether someone has it or not is made up of so many components that no single question can uncover it all.
But there are questions that get you closer. Questions that reveal how someone thinks, how they work, and whether they've actually done what their CV says they've done. And there are questions that waste everyone's time because they come too late or don't test anything useful.
This post is about asking the right questions at the right stage of the process. Because the biggest problem I see with interview questions in building products isn't what gets asked in the interview room. It's what doesn't get asked before you get there.
Screen first. Interview second.
The most valuable questioning happens before the formal interview.
A 10 to 15 minute phone screen should knock out the obvious deal breakers before anyone commits to a sit-down meeting. This saves you hours. It saves the candidate hours. And it stops the most common frustration I see in building products hiring: a deal breaker surfacing at the end of a process that should have ended in week one.
The phone screen should cover:
Salary expectations. "What are you looking for in terms of base salary and total package?" Direct. No ambiguity. If the gap between what they want and what you're offering is more than 10-15%, it's unlikely to work. Better to know now.
Work from home expectations. "This role requires X days in the office. Does that work for you?" The number of times this comes out at offer stage is remarkable. Ask it in the first conversation.
Travel and territory. "The territory covers X. Are you comfortable with that level of travel?" If the role is regional and they want to stay metro, that's a fundamental mismatch.
Availability and timeline. "When could you start? Are you in any other processes?" This helps you plan your timeline and understand urgency.
If the phone screen checks out, now you interview properly. Everything that follows should be about capability, experience, and fit. Not logistics.
Questions that test real sales ability
Once you're in the interview, here are the questions that actually tell you something useful for building products sales roles.
"Walk me through your average day."
This reveals how they structure their time. Are they proactive or reactive? Do they plan their week or respond to whatever comes in? How many calls, visits, and meetings are they doing? A BDM who can't clearly describe how they manage a territory day to day is a concern.
"Talk me through your sales process from identifying an opportunity to closing it."
You're testing whether they have a repeatable method. Do they qualify properly? Do they follow up systematically? Do they use a CRM? Or are they relying on memory and charm? Both can work, but one is scalable and the other isn't.
"Tell me about your key relationships. Who have you built strong connections with?"
In building products, relationships are currency. This question tests whether they can name specific people, companies, and the depth of those connections. "I've got great relationships with architects" is vague. "I work closely with three of the top-10 commercial architecture firms in Melbourne, specifically the specification teams" is specific and verifiable.
Listen for the detail. Real relationships come with stories, context, and specifics. Fabricated ones come with generalities.
"What were your numbers last year? Budget, actual, growth."
Non-negotiable. If someone is in sales and can't talk clearly about their targets and performance, something is off. They should know their budget, what they delivered, and the story behind the numbers.
The good answer sounds like: "My budget was $1.8M. I finished the year at $2.1M, about 17% above target. The growth came from converting two major commercial accounts and reactivating a lapsed builder relationship."
The bad answer sounds like: "I was doing well. The territory was growing." No specifics. No context. No confidence in the numbers.
You don't need them to know every figure to the dollar. But they should have a clear grasp of what they were responsible for and what they delivered.
"Tell me about a territory or account base you inherited that needed work. What did you do?"
This is more revealing than "tell me about a time you exceeded target." Anyone can perform in a healthy territory. The question is whether they can build. In building products, territories often need rebuilding. Lapsed accounts, competitor-dominated areas, underdeveloped segments. You need someone who can start from scratch and grow.
"How do you handle a situation where a customer is unhappy with the product or a delivery has gone wrong?"
Sales in building products isn't just about winning new business. It's about managing problems. Supply delays. Product issues. Installation complications. The candidates who stand out are the ones who own the problem, communicate clearly, and maintain the relationship through difficulty.
Questions that are a waste of time
Any deal-breaker question asked at the final stage. If you're in the second or third interview and you're still asking about salary expectations, something has gone wrong with your process. These should be cleared in the phone screen.
"Where do you see yourself in five years?" This tells you nothing useful. Most candidates give a rehearsed answer about growing within the company. What you actually want to know is whether they're likely to stay and whether the role matches their trajectory. Ask that directly instead: "What are you looking for in your next role that you're not getting now?"
Generic competency questions. "Tell me about a time you showed leadership." "Describe a challenge you overcame." These can work in some contexts, but for sales roles in building products, you'll learn more from specific, role-relevant questions than from generic frameworks.
Red flags in how candidates answer
Saying yes to everything. When a candidate agrees with every requirement, every condition, and every expectation without a single question or pushback, be cautious. I see it regularly. A candidate tells me privately that they want two days from home. In the interview, when asked if they're happy in the office five days, they say yes.
People do this because they want the job. But it should concern you. If they're telling you what you want to hear now, what else might not be genuine? The best candidates push back respectfully. They ask clarifying questions. They negotiate. That's what good salespeople do.
Vague answers on numbers. As above. If they can't or won't talk about their performance in concrete terms, the numbers probably aren't worth sharing.
Contradictions. Watch for inconsistencies between what's on the CV and what they say in the interview. Different timelines. Roles mentioned that aren't listed. Responsibilities that don't match the job title. These don't always mean dishonesty, but they warrant follow-up questions.
Bluffing technical knowledge. If you ask about a product or application and they clearly don't know the answer but try to talk their way through it, that's a concern. Not because they should know everything, but because a good salesperson knows when to say "I don't know but here's how I'd find out." Bluffing in an interview usually means bluffing in front of customers.
Assessing culture fit
There's no question that reliably predicts culture fit. It's a feeling. You'll get it from the conversation, from how they interact, from whether the chemistry is there.
But you can improve your odds.
Introduce them to the team. Before making an offer, have the candidate meet two or three of their future colleagues informally. A coffee or a quick chat. This gives both sides a chance to assess fit in a low-pressure setting.
Ask the candidate what they know about you. The good ones will have done their homework. They'll have asked around. They'll know people in the industry who've worked at your company. In building products, the sector is small enough that most people are one or two connections away from someone with an opinion.
Trust your instinct but verify it. If something feels off, probe further. If everything feels right, still check references. Gut feel is a useful signal, not a reliable decision-making tool on its own.
The question the candidate asks that should impress you
When a candidate asks "What would have to happen by the end of this year for me to look back and consider this a success?", pay attention.
That question shows they're thinking about outcomes, not just tasks. They're focused on what matters to you, not just what's in it for them. It shifts the conversation from generic ambition to specific expectations.
The candidates who ask these kinds of questions are usually the ones who deliver once they're in the role. They think about the bigger picture. They want to understand what success looks like from your perspective, not just theirs.
If a candidate asks you this and you can't answer it clearly, that might tell you something about how well you've defined the role.
Quick checklist for hiring managers
- Phone screen first. Clear salary, work from home, travel, and timeline before scheduling an interview.
- Ask about their average day, their sales process, their key relationships, and their numbers. These are non-negotiable.
- Test whether they can build, not just maintain. Ask about inherited territories and account bases that needed work.
- Watch for candidates who say yes to everything. Respectful pushback is a better sign than blanket agreement.
- Don't ask deal-breaker questions at the final stage. If it should have been covered in the phone screen, go back and fix your process.
- Introduce candidates to the team before making an offer. Culture fit is a feeling, but you can create better conditions to assess it.
- Pay attention to the questions they ask you. Long-term thinking and genuine curiosity are green flags.