Martyn Butler, founder · Updated 25 September 2026 · 6 minute read
What an interview can and cannot tell you
A conversation is good at some things. You hear their spoken English, you get a sense of how they come across, and you can ask about the work they say they have done. If the role involves phone calls, that matters.
It is poor at the things that decide whether a VA works out. Confident talkers do well in interviews, and so do people who have practised the usual questions. Careful, quiet people often do worse than they would in the job. None of it shows you whether they read instructions, how they write, or what they do when the answer is not obvious.
Written applications have the same weakness now that AI tools will draft a polished answer in seconds. A good-looking answer tells you less than it used to. A task done to a deadline, on your material, tells you a great deal more.
What makes a good test task
- It is drawn from the real job. If they will answer customer emails, test that, not a general writing exercise.
- It is short: somewhere between 30 and 90 minutes of work. Long enough to show how they think, short enough that good candidates will do it.
- The brief is written down, complete, and the same for everyone, so you compare like with like.
- It uses made-up names and details, never your real customers' data. Do not send personal information to people you have not hired.
- You decide how you will score it before anybody starts.
- It is paid.
Five tasks worth setting
Pick one or two that match the role. Each one tests something different.
- A reply to an awkward customer. Give them a complaint, your refund policy and a limit on what they may offer. It tests tone, written English, and whether they stay inside the rules or promise something you cannot give.
- A messy inbox to sort. Twenty made-up emails: some urgent, some junk, a supplier invoice, a customer asking the same thing twice. Ask them to label each one, draft three replies and list what needs you. It tests judgement and priorities.
- A diary clash. Two meetings in the same slot, a client who can only do Tuesdays, and a rule that nothing is booked before 10am. It tests whether they spot the conflict, apply the rules and write a clear message proposing the fix.
- A written procedure, followed exactly. Give them a one-page procedure for a routine job, such as logging a repair or adding a booking to a spreadsheet, and the details to process. It tests the thing that matters most in a VA: doing it your way, every time, without improvising.
- A small spreadsheet tidy. Fifty rows of contacts with duplicates, mixed date formats and missing postcodes. It tests attention to detail, and whether they tell you what they changed.
Hide an instruction in the brief
Put one small, specific instruction in the brief: name the file a certain way, keep the reply under 120 words, or put a particular word in the subject line. Do not draw attention to it.
Whether they follow it tells you how closely they read, which is most of what you are paying a VA for. Somebody who misses a clear instruction in a test they know is being judged will miss one in your procedures.
We do the same in our own hiring. Our application form is written to be read closely, and the instructions in it are part of what we check.
How to score it fairly
Decide the criteria first and score every candidate against the same ones. A four-point scale is enough. Here are the two ends of it:
| Criterion | 1: weak | 4: strong |
|---|---|---|
| Followed the brief | Missed instructions, or answered a different question | Did exactly what was asked, small details included |
| Accuracy | Mistakes a customer would notice | No mistakes, and flagged the ones in your material |
| Judgement | Guessed, or promised what the rules do not allow | Stayed inside the limits and said clearly what needed you |
| Writing | Unclear, stiff or generic | Plain, polite and specific to the situation |
| Timing | Late, with no word | On time, or said early that it would be late |
Keep the scoring honest
- Take the names off before you mark, so you judge the work and not the person you liked on the phone.
- Mark one task across every candidate before you move to the next, so your standard does not drift.
- Write one line of evidence beside each score. If you cannot point to it in the work, it is not a score.
- If you can, have a second person mark it as well and compare. A big difference means the criteria need tightening.
How long, and what to pay
Keep it to something that can be done in 30 to 90 minutes, and say how long you expect it to take. Give a deadline of a day or two, so people who already have work can fit it in.
Pay for it. Pay the job's hourly rate for the time you said it would take, or agree a fixed fee before they start, and pay promptly whether or not you hire them. It shows what kind of business you are, and the best candidates, who have other options, take a paid task more seriously.
Never use test work in your business without paying for it, and never set a task that is really a free day of your backlog. If you are hiring somebody in the UK, government guidance says a short unpaid trial of a few hours may not need paying if it genuinely tests skills, but the longer it runs, the more likely the minimum wage is due. Paying removes the question. If you are unsure, take advice.
Red flags
- Missing the instruction you hid in the brief.
- Answers that could fit any business: polished, general, and missing the details you gave them.
- Promising a customer something your policy does not allow.
- Going quiet past the deadline, then sending it without a word.
- Asking questions the brief already answers. A good question about something the brief left out is the opposite: a good sign.
- Work far better than the rest of their application, which they cannot explain when you ask how they did it.
Then talk to them about the work
Keep the interview, but hold it after the task and make the task its subject. Ask why they answered the customer the way they did, what they would change with more time, and what they found unclear.
You learn how they think, and whether the work was really theirs, in a way the standard interview questions never show. It also gives a nervous candidate something concrete to talk about, which is fairer to them.
How we do it
At Mango & Co., the screening happens before you meet anybody: by then a candidate has passed a timed test, references and an interview with us, so you meet a shortlist of the strongest. When you want to go ahead with one of them, the paid task comes next: work drawn from your real business, paid for the time it takes, and done before any offer is made. The offer follows only if the work is right.
If you would like to know whether a VA would work for your business, and which jobs you would hand over first, our free plan at /fit takes about three minutes.