index.js

const axios = require('axios');

const requestBody = {
  "listingType":"Rent",
  "propertyTypes":[
    "Townhouse",
    "ApartmentUnitFlat"
  ],
  "minBedrooms": 2,
  "minPrice": 500,
  "maxPrice": 620,
  "locations":[
    {
      "state":"VIC",
      "region":"",
      "area":"",
      "suburb":"Richmond",
      "postCode":"3121",
      "includeSurroundingSuburbs":true
    }
  ],
  "pageSize": "200"
}

const axiosConfig = {
    "headers": {
        "X-API-Key": process.env.API_KEY
    }
}

const search = async () => {
    const request = await axios.post("https://api.domain.com.au/v1/listings/residential/_search", requestBody, axiosConfig)
    console.log(request.data)
}

search()

package.json

{
  "name": "domain",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "axios": "^0.19.2",
    "dotenv": "^8.2.0"
  }
}