money.js

export default function (value) {
  const formatted = Number(value)
    .toFixed(2)
    .replace('.', ',')
    .replace(/(\d)(?=(\d\d\d)+(?!\d))/g, "$1.")
  return `R$ ${formatted}`
}

numberInFormat.vue

<template>
  <div>
      <p>Product one cost: {{ productOneCost | money }}</p>
      <p>Product two cost: {{ productTwoCost | money }}</p>
      <p>Product three cost: {{ productThreeCost | money }}</p>
  </div>
</template>

<script>
import money from 'formatters/money'

export default {
  data: () => ({
    productOneCost: 998,
    productTwoCost: 2399,
    productThreeCost: 5300
  }),
  filters:{
    money(value){
      return money(value)
    }
  }
}
</script>