*/ (function(){ const $ = (id) => document.getElementById(id); const fmt = (n, opts={}) => { const v = (isFinite(n) ? n : 0); const o = { style:'currency', currency:'USD', maximumFractionDigits:0, ...opts }; return new Intl.NumberFormat('en-US', o).format(v); }; const pct = (n, d=2) => `${(isFinite(n)? n : 0).toFixed(d)}%`;function payment(principal, annualRatePct, years) { const r = (annualRatePct/100)/12; const n = years*12; if (r === 0) return principal/n; return principal * (r * Math.pow(1+r, n)) / (Math.pow(1+r, n) - 1); } function balanceAfter(principal, annualRatePct, years, monthsElapsed) { const r = (annualRatePct/100)/12; const n = years*12; if (r === 0) return principal * (1 - monthsElapsed/n); const pmt = payment(principal, annualRatePct, years); return principal*Math.pow(1+r, monthsElapsed) - pmt*( (Math.pow(1+r, monthsElapsed) - 1)/r ); } function cumulativePrincipalPaid(principal, annualRatePct, years, monthsElapsed){ return principal - balanceAfter(principal, annualRatePct, years, monthsElapsed); }const ids = [ 'price','downPct','rate','term','rent','otherIncome','vacancy','mgmtPct', 'taxesAnnual','insAnnual','hoaMonthly','maintPct','repairsMonthly','otherMonthly','closingPct','initialRepairs', 'holdYears','appreciation','rentGrowth','expGrowth','sellCostPct','landPct','incomeTaxPct','cgTaxPct' ]; const out = { cashflow: $('m-cashflow'), caprate: $('m-caprate'), coc: $('m-coc'), dscr: $('m-dscr'), ads: $('m-ads'), noi: $('m-noi'),gsr: $('o-gsr'), vac: $('o-vac'), egi: $('o-egi'), opex:$('o-opex'), mort:$('o-mort'), oNoi:$('o-noi'),ltSale: $('lt-sale'), ltBal: $('lt-balance'), ltSell: $('lt-sellcosts'), ltCF: $('lt-cf'), ltPrin: $('lt-principal'), ltNet: $('lt-net'), ltProfit: $('lt-profit'), ltRoi: $('lt-roi'), ltAnn: $('lt-annualized'),cashNeeded: $('m-cashneeded') }; if (!out.cashflow) return;// Defaults const defaults = { price: 300000, downPct: 25, rate: 7.25, term: 30, rent: 2200, otherIncome: 0, vacancy: 5, mgmtPct: 8, taxesAnnual: 3600, insAnnual: 1500, hoaMonthly: 0, maintPct: 8, repairsMonthly: 100, otherMonthly: 0, closingPct: 3, initialRepairs: 0, holdYears: 5, appreciation: 3, rentGrowth: 2, expGrowth: 2, sellCostPct: 8, landPct: 20, incomeTaxPct: 24, cgTaxPct: 15 };// Initialize placeholders ids.forEach(id => { const el=$(id); if(el && !el.value) el.value = defaults[id] ?? ''; });function valNum(id){ const el = $(id); if(!el) return 0; const v = parseFloat(String(el.value).replace(/,/g,'')); return isFinite(v) ? v : 0; }function recalc(){ // Inputs const price = valNum('price'); const downPct = valNum('downPct'); const rate = valNum('rate'); const term = valNum('term');const rent = valNum('rent'); const otherIncome = valNum('otherIncome'); const vacancy = valNum('vacancy'); const mgmtPct = valNum('mgmtPct');const taxesAnnual = valNum('taxesAnnual'); const insAnnual = valNum('insAnnual'); const hoaMonthly = valNum('hoaMonthly'); const maintPct = valNum('maintPct');const repairsMonthly = valNum('repairsMonthly'); const otherMonthly = valNum('otherMonthly'); const closingPct = valNum('closingPct'); const initialRepairs = valNum('initialRepairs');const holdYears = valNum('holdYears'); const appreciation = valNum('appreciation'); const rentGrowth = valNum('rentGrowth'); const expGrowth = valNum('expGrowth'); const sellCostPct = valNum('sellCostPct');// Financing const downPayment = price * (downPct/100); const loanAmount = Math.max(price - downPayment, 0); const mortPmt = (loanAmount>0 && term>0) ? payment(loanAmount, rate, term) : 0; const ads = mortPmt * 12;// Income (monthly) const grossMonthly = rent + otherIncome; const vacancyLoss = grossMonthly * (vacancy/100); const egiMonthly = grossMonthly - vacancyLoss;// Operating expenses (monthly) const mgmtMonthly = rent * (mgmtPct/100); // mgmt on rent only (common) const maintMonthly = rent * (maintPct/100); const taxesMonthly = taxesAnnual/12; const insMonthly = insAnnual/12;const opexMonthly = mgmtMonthly + maintMonthly + taxesMonthly + insMonthly + hoaMonthly + repairsMonthly + otherMonthly;// NOI (annual, pre-debt) const noiAnnual = (egiMonthly - opexMonthly) * 12;// Metrics const capRate = price>0 ? (noiAnnual/price)*100 : 0; const monthlyCashFlow = egiMonthly - opexMonthly - mortPmt; const cashNeeded = downPayment + (price * (closingPct/100)) + initialRepairs; const coc = cashNeeded>0 ? ((monthlyCashFlow*12)/cashNeeded)*100 : 0; const dscr = ads>0 ? (noiAnnual/ads) : 0;// Long-term (simplified projections) const months = holdYears*12; const futurePrice = price * Math.pow(1 + (appreciation/100), holdYears); const sellCosts = futurePrice * (sellCostPct/100); const loanBal = balanceAfter(loanAmount, rate, term, months); const principalPaid = cumulativePrincipalPaid(loanAmount, rate, term, months);// Grow rent & expenses with separate growth rates (straight-line monthly comp approx) const growthRentMonthly = rent * Math.pow(1 + (rentGrowth/100), holdYears); const avgRentMonthly = (rent + growthRentMonthly)/2; // simple average over period const avgOtherIncMonthly = otherIncome; // assume flat const avgGrossMonthly = avgRentMonthly + avgOtherIncMonthly; const avgVacLoss = avgGrossMonthly * (vacancy/100); const avgMgmtMonthly = avgRentMonthly * (mgmtPct/100); const growthMaintMonthly = (rent * (maintPct/100)) * Math.pow(1 + (expGrowth/100), holdYears); const avgMaintMonthly = (rent*(maintPct/100) + growthMaintMonthly)/2;const growthTaxesMonthly = taxesMonthly * Math.pow(1 + (expGrowth/100), holdYears); const avgTaxesMonthly = (taxesMonthly + growthTaxesMonthly)/2;const growthInsMonthly = insMonthly * Math.pow(1 + (expGrowth/100), holdYears); const avgInsMonthly = (insMonthly + growthInsMonthly)/2;const growthHOA = hoaMonthly * Math.pow(1 + (expGrowth/100), holdYears); const avgHOA = (hoaMonthly + growthHOA)/2;const growthRep = repairsMonthly * Math.pow(1 + (expGrowth/100), holdYears); const avgRep = (repairsMonthly + growthRep)/2;const growthOther = otherMonthly * Math.pow(1 + (expGrowth/100), holdYears); const avgOther = (otherMonthly + growthOther)/2;const avgEGIMonthly = avgGrossMonthly - avgVacLoss; const avgOpexMonthly = avgMgmtMonthly + avgMaintMonthly + avgTaxesMonthly + avgInsMonthly + avgHOA + avgRep + avgOther; const avgNOIAnnual = (avgEGIMonthly - avgOpexMonthly) * 12; const avgMonthlyCashFlow = avgEGIMonthly - avgOpexMonthly - mortPmt;const cfCumulative = avgMonthlyCashFlow * months; const netProceeds = Math.max(futurePrice - sellCosts - loanBal, 0); const totalProfitPreTax = cfCumulative + principalPaid + (netProceeds); // double counts? No: netProceeds already subtracts remaining loan; principalPaid counts via cash flow equity growth — we keep both cash flow + net proceeds (which is equity at sale). principalPaid is embedded in netProceeds vs original loan? Common approaches vary; we’ll show both CF and Net separately below and include principal explicitly. // To avoid double counting principal: treat netProceeds as (future equity realized) and ONLY add CF. We'll present principalPaid separately in UI. const totalProfit = cfCumulative + netProceeds; // preferred: CF + Net Sale (no double-count) const roiTotal = cashNeeded>0 ? (totalProfit / cashNeeded) * 100 : 0; const annualizedSimple = holdYears>0 ? (roiTotal/holdYears) : 0;// Outputs out.cashflow.textContent = fmt(monthlyCashFlow, {maximumFractionDigits:0}); out.caprate.textContent = pct(capRate, 2); out.noi.textContent = `NOI: ${fmt(noiAnnual, {maximumFractionDigits:0})}/yr`; out.coc.textContent = pct(coc, 2); out.cashNeeded.textContent = `Cash Invested: ${fmt(cashNeeded, {maximumFractionDigits:0})}`; out.dscr.textContent = `${(isFinite(dscr)? dscr : 0).toFixed(2)}×`; out.ads.textContent = `Annual Debt Service: ${fmt(ads, {maximumFractionDigits:0})}`;out.gsr.textContent = fmt(grossMonthly, {maximumFractionDigits:0}); out.vac.textContent = `−${fmt(vacancyLoss, {maximumFractionDigits:0})}`; out.egi.textContent = fmt(egiMonthly, {maximumFractionDigits:0}); out.opex.textContent = `−${fmt(opexMonthly, {maximumFractionDigits:0})}`; out.oNoi.textContent = fmt(noiAnnual, {maximumFractionDigits:0}); out.mort.textContent = `−${fmt(mortPmt, {maximumFractionDigits:0})}`;out.ltSale.textContent = fmt(futurePrice, {maximumFractionDigits:0}); out.ltBal.textContent = fmt(Math.max(loanBal,0), {maximumFractionDigits:0}); out.ltSell.textContent = `−${fmt(sellCosts, {maximumFractionDigits:0})}`; out.ltCF.textContent = fmt(cfCumulative, {maximumFractionDigits:0}); out.ltPrin.textContent = fmt(Math.max(principalPaid,0), {maximumFractionDigits:0}); out.ltNet.textContent = fmt(netProceeds, {maximumFractionDigits:0});out.ltProfit.textContent = fmt(totalProfit, {maximumFractionDigits:0}); out.ltRoi.textContent = pct(roiTotal, 2); out.ltAnn.textContent = pct(annualizedSimple, 2); }// Wire up listeners ids.forEach(id=>{ const el = $(id); if(!el) return; el.addEventListener('input', recalc); el.addEventListener('change', recalc); });// Buttons const btnSample = document.getElementById('rpc-load-sample'); const btnReset = document.getElementById('rpc-reset');btnSample && btnSample.addEventListener('click', ()=>{ Object.entries(defaults).forEach(([k,v])=>{ const el=$(k); if(el) el.value=v; }); recalc(); const adv = document.getElementById('rpc-adv'); if(adv && !adv.open) adv.open = true; }); btnReset && btnReset.addEventListener('click', ()=>{ ids.forEach(id=>{ const el=$(id); if(el){ el.value=''; }}); // sensible blank state recalc(); });// Initial if (out.cashflow) { recalc(); } })();