What a missed plumbing call costs
If you run a plumbing truck, you can write this down with numbers you already know. Each letter is a figure from your own week.
Write down four numbers
J is what a typical job is worth to you, in dollars, after you have decided what "typical" means for your work. C is how many inbound calls you get on a working day. M is the share of those calls you do not answer, as a fraction between 0 and 1. A is the share of answered calls that become a booked job. V is the share of missed calls that still become a booked job, usually because the caller left a message and you got back to them in time.
If you do not know M, A, or V, count them for a week before you trust the result. A guess in any of those boxes makes the whole line a guess.
The two totals
Calls you miss in a day are C times M. If those calls had been answered, the booked jobs you would expect are C times M times A, and the dollars are that count times J.
The same missed calls, left as voicemail, produce C times M times V booked jobs, times J dollars.
The gap for one day is C times M times (A minus V) times J. Multiply by the number of working days in your month if you want a month. If A is not larger than V, the gap is zero and the voicemail is not the problem.
What you can do with the gap
A missed-call text from your phone provider asks the caller to write back. You still have to reply yourself, and you still miss the call that needed someone on the line.
Kyra on Pro is $499 a month. It includes a business number for calls and texts, and 300 voice minutes. Growth at $299 a month covers web chat only, so it is the wrong plan if the gap you just wrote down is phone calls. Compare $499 with the daily gap you calculated. If the gap is smaller than the plan, the plan does not pay for itself on this math.
A person who answers the phone covers the hours you schedule them for. Kyra on Pro answers the number you assign it, including after you have left the job, using the greeting and the rules you set.
If you want to hear it
The trial is 7 days. You can put Kyra on a new number, forward a few calls, and read the transcripts before you point your main number at it. Cancel before the trial ends and the card is not charged.