Airbtics Airbnb calculator - v1

airbnb-calculator.js

function calculateRev(values){
  let valuesLen = Object.keys(values).length;
  if (valuesLen < 13){
    console.log("not enough filled ", valuesLen)
    return false
  }

  for (var key in values) {
          values[key] = Number(values[key])
    }

  let adr = values.adr;
  let availableDay = 365*values.availability*0.01;
  let occupancy = values.occupancy*0.01;

  let tax = values.profitTax;
  let mortgageCost = (values.housePrice-values.downPayment)*0.01*values.interestRate

  let firstYearRev = adr*availableDay*occupancy;

  let yearGrowingExpense = values.annualCost+values.monthlyCost*12
  let yearExp = yearGrowingExpense+mortgageCost

  let yearProfitBeforeTax = firstYearRev-yearExp;
  let taxThisYear = (yearProfitBeforeTax>0) ? yearProfitBeforeTax*0.01*tax : 0

  let firstYearTax = taxThisYear;
  let firstYearExpense = yearExp;
  yearExp = yearExp + taxThisYear;
  let totalOneOffCost = values.downPayment + values.oneOffCost;
  let cac = (yearProfitBeforeTax/totalOneOffCost)*100;
  let netRentalYield = (yearProfitBeforeTax/values.housePrice)*100;
  let profitAfterTax = yearProfitBeforeTax-taxThisYear

  let totalRevenues = [firstYearRev]
  let totalExpenses = [yearExp]
  let totalProfits = [profitAfterTax]
  let firstYearProfitAfterTax = profitAfterTax

  let currentPropertyPrice = values.housePrice;
  let profitAccum = totalProfits.reduce((a, b) => a + b, 0);
  console.log("year 1 profit = " + profitAfterTax + " accum = " + profitAccum)
  let revenueObjs = [
    {
      "year":1,
      "revenue": firstYearRev,
      "expense": yearExp,
      "profitAccum": profitAccum,
      "propertyEvaluation": currentPropertyPrice
    }
  ]


  for (let i = 2; i < 31; i++) {

    adr = adr + (adr*0.01*values.annualADRIncrease);
    let yearRev = adr*availableDay*occupancy;
    yearGrowingExpense = yearGrowingExpense + (yearGrowingExpense*0.01*values.expenseIncrease)
    yearExp = yearGrowingExpense + mortgageCost
    console.log("exp " + yearExp + " yearGrowingExpense " + yearGrowingExpense + "  mortgageCost " + mortgageCost )

    let profit = yearRev-yearExp;
    console.log("rev " + yearRev + " exp " + yearExp)
    taxThisYear = profit*0.01*tax;
    let yearExpWithTax = yearExp + taxThisYear;
    profitAfterTax = profit-taxThisYear;
    currentPropertyPrice = currentPropertyPrice + currentPropertyPrice*0.01*values.annualAppreciation;

    totalProfits.push(profitAfterTax)
    totalRevenues.push(yearRev)
    totalExpenses.push(yearExpWithTax)
    profitAccum = totalProfits.reduce((a, b) => a + b, 0);
    console.log("year " + i + " profit = " + profitAfterTax + " accum = " + profitAccum)

    revenueObjs.push(
      {
        "year":i,
        "revenue": Math.round(yearRev),
        "expense": Math.round(yearExp),
        "profitAccum": Math.round(profitAccum),
        "propertyEvaluation": Math.round(currentPropertyPrice)

      }
    )
  }



  let returnObj = {
    'cac': Math.round(cac),
    'firstYearRev': Math.round(firstYearRev),
    'firstYearProfitAfterTax' : Math.round(firstYearProfitAfterTax),
    'firstYearTax' : Math.round(firstYearTax),
    'firstYearExpense':  Math.round(firstYearExpense),
    'netRentalYield': Math.round(netRentalYield),
    'revenueObjs' : revenueObjs,
  }
  return returnObj
}

TODO: typescript / make name self explainable. This was just a quick MVP.