@u-dev/unison-calculators

unison-calculators

Utility Calculator

UtilCalculator

The util calculator can be used to do basic math for Unison deals.

For instance, I could run:

let calculator = new UtilCalculator('HomeOwner')
calculator.minHomeValue(3.5) // => 114285
calculator.maxHomeValue(3.5) // => 2857142
calculator.minSharingPercentage(3.5) // => 0.175
calculator.minInvestmentAmount(500000) // => 25000
calculator.maxInvestmentAmount(500000) // => 100000
calculator.sharingPercentage(.2, 3.5) // => .7
calculator.investmentPercentage(500000,100000) // => .2
calculator.unisonShare(100000,.35) // => 35000
calculator.leverage() // => 4
calculator.leverage({qualifiesForNewPricing: true}) // => 3.5

let calculator = new UtilCalculator('HomeBuyer')
calculator.minHomeValue(3.5) // => 114285
calculator.maxHomeValue(3.5) // => 2857142
calculator.minSharingPercentage(3.5) // => 0.175
calculator.minInvestmentAmount(500000) // => 25000
calculator.maxInvestmentAmount(500000) // => 100000
calculator.sharingPercentage(.2, 3.5) // => .7
calculator.investmentPercentage(500000,100000) // => .2
calculator.unisonShare(100000,.35) // => 35000
calculator.leverage() // => 4
calculator.leverage({isNewConstruction: true}) // => 4.5

API documentation:

// .initialize
// @param {string} product - The product we are calculating for
new UtilCalculator('HomeOwner')

// #minHomeValue()
// @param {number} leverage - The leverage in a unison deal
calculator.minHomeValue(3.5)

// #maxHomeValue()
// @param {number} leverage - The leverage in a unison deal
calculator.maxHomeValue(3.5)

// #minSharingPercentage()
// @param {number} leverage - The leverage in a unison deal
calculator.minSharingPercentage(3.5)

// #minInvestmentAmount()
// @param {number} homeValue - The home value
calculator.minInvestmentAmount(500000)

// #maxInvestmentAmount()
// @param {number} homeValue - The home value
calculator.maxInvestmentAmount(500000)

// #sharingPercentage()
// @param {number} investmentPercentage - The amount unison invested in a deal
// @param {number} leverage - The leverage on a deal
calculator.sharingPercentage(.2, 3.5)

// #investmentPercentage()
// @param {number} appreciation - The amount that the asset appreciated
// @param {number} sharingPercentage - The percentage share unison has given a deal
calculator.investmentPercentage(.2, 3.5)

// #unisonShare()
// @param {number} homeValue - The value of the asset
// @param {number} amountInvested - The amount invested in the home
calculator.unisonShare(100000, .35)

// #leverage()
// @param {object} options  
// @param {string} [options.qualifiesForNewPricing] - This acts as a leverage modifier on HomeOwner deals
// @param {string} [options.isNewConstruction] - This acts as a leverage modifier on HomeBuyer deals
calculator.leverage({qualifiesForNewPricing: true})

Scenario Calculators

HomeBuyerScenarioCalculator

The HomeBuyer scenario calculator can be used to calculate the outcome of a homebuyer deal.

To get started initialize a HomeBuyerCalculator instance and run the #calculate function.

#calculate takes four arguments 1) initialHomeValue, 2) unisonInvestment, 3) finalPriceChange, 4) and optional configuration object

For instance, I could run:

let calculator = new HomeBuyerScenarioCalculator()
calculator.calculate(500000,50000,100000,{
  isNewConstruction: false
})

And expect

{
  finalPriceChange: 100000,
  initialHomeValue: 500000,
  unisonInvestment: 50000,
  unisonLeverage: 4,
  unisonSharingPercentage: 0.4,
  unisonInvestmentPercentage: 0.1,
  futureSalePrice: 600000,
  unisonPayment: 90000,
  unisonShareInChange: 40000
}

API documentation:

// .initialize
new HomeBuyerScenarioCalculator()

// #calculate()
// @param {number} initialHomeValue - The initial home value
// @param {number} unisonInvestment - The amount unison has invested
// @param {number} finalPriceChange - The change in value you want to calculate for
// @param {object} [options={}] - optional modifiers for calculations
// @param {boolean} [options.isNewConstruction=false] - toggles pricing (non-new construction homes have better pricing)
calculator.calculate(500000, 50000, 100000, {
  isNewConstruction: false
})

HomeOwnerScenarioCalculator

The HomeOwner scenario calculator can be used to calculate the outcome of a homebuyer deal.

To get started initialize a HomeBuyerCalculator instance and run the #calculate function.

#calculate takes four arguments 1) initialHomeValue, 2) unisonInvestment, 3) finalPriceChange, 4) and optional configuration object

For instance, I could run:

let calculator = new HomeOwnerScenarioCalculator()
calculator.calculate(500000, 50000, 100000, {
  qualifiesForNewPricing: false
})

And expect

{
  finalPriceChange: 100000,
  initialHomeValue: 500000,
  unisonInvestment: 50000,
  unisonLeverage: 4,
  unisonSharingPercentage: 0.4,
  unisonInvestmentPercentage: 0.1,
  futureSalePrice: 600000,
  unisonPayment: 90000,
  unisonShareInChange: 40000
}

API documentation:

// .initialize
new HomeOwnerScenarioCalculator()

// #calculate()
// @param {number} initialHomeValue - The initial home value
// @param {number} unisonInvestment - The amount unison has invested
// @param {number} finalPriceChange - The change in value you want to calculate for
// @param {object} [options={}] - optional modifiers for calculations
// @param {boolean} [options.qualifiesForNewPricing=false] - toggles pricing (this is new pricing A.K.A. purchased in last year, which has better pricing)
calculator.calculate(500000, 50000, 100000, {
  qualifiesForNewPricing: false
})

Mortgage Calculators

HomeBuyerMortgageCalculator

The homebuyer mortgage calculator can be used to calculate mortgage payments with and without Unison.

To get started, initialize a new calculator with (optionally) an object containing any assumptions you want to overwrite.

You can then use the #calculate function to see payment outcomes for various combinations.

#calculate takes three arguments 1) homePrice, 2) clientDownPaymentPercentage, and 3) unisonDownPaymentPercentage

For instance, I could run:

var calculator = new HomeBuyerMortgageCalculator({assumptions: {mortgageYears: 30}})
calculator.calculate(500000,.1,.1)

And expect:

{
  assumptions: {
    mortgageYears: 30,
    annualMortgageInsurancePremium: 0.0074,
    annualMortgageInterestRate: 0.04,
    annualPropertyInsuranceRate: 0.003,
    annualPropertyTaxRate: 0.0125,
  },
  monthlyMortgagePayment: -1910,
  monthlyPMIPayment: 0,
  monthlyPropertyTaxPayment: -521,
  monthlyPropertyInsurancePayment: -125,
  totalMonthlyPayments: -2556,
  clientDownPaymentAmount: 50000,
  unisonDownPaymentAmount: 50000,
  downPaymentAmount: 100000,
  hasPMI: false,
}

Here are the default assumptions for any new calculator:

const DEFAULT_ASSUMPTIONS = {
  mortgageYears: 30,
  annualMortgageInterestRate: .04,
  annualPropertyTaxRate: .0125,
  annualPropertyInsuranceRate: .003,
  annualMortgageInsurancePremium: .0074,
}

API documentation:

// .initialize
// @param {object} [options={assumptions={}}] - The default set of options
// @param {number} [options.assumptions.mortgageYears] - Length of mortgage in years
// @param {number} [options.assumptions.annualMortgageInterestRate] - Annual loan interest rate
// @param {number} [options.assumptions.annualPropertyTaxRate] - Annual property tax rate
// @param {number} [options.assumptions.annualPropertyInsuranceRate] - Annual property insurance rate
// @param {number} [options.assumptions.annualMortgageInsurancePremium] - PMI rate
new HomeBuyerMortgageCalculator(options)

// #calculate()
// @param {number} homePrice - The initial home value
// @param {number} clientDownPaymentPercentage - The percent of the loan, expressed as a decimal, that the client paid down
// @param {number} unisonDownPaymentPercentage - The percent of the loan, expressed as a decimal, that unison paid down
calculator.calculate(500000,.1,.1)