Investment analyzer

Model the deal before you chase it

A deterministic calculator for buy-to-rent and fix-and-flip strategies. Every result recalculates instantly from the assumptions you enter — nothing here is a forecast or a valuation.

Start from a real property record

Illustrative Assumptions — enter your own figures. The starting values are generic South Florida examples, not data about any property. Replace them with quotes and comparables for the deal you are considering, or open a parcel record to seed the calculator from public records.

Acquisition

Purchase price

Your assumption

Closing costs

Your assumption

Share of price

Renovation / make-ready

Your assumption

Financing

Down payment

Your assumption

100% = all cash

Interest rate

Your assumption

Loan term

Your assumption

Loan points

Your assumption

Share of loan, paid at closing

Income

Monthly rent (all units)

Your assumption

Other income

Your assumption

Parking, laundry, storage

Vacancy & credit loss

Your assumption

Taxes, insurance & HOA

Property tax

Your assumption

Florida reassesses after a sale — seller caps do not transfer

Insurance (windstorm + flood)

Your assumption

Get a wind/flood quote; premiums vary widely

HOA / condo fees

Your assumption

Check reserves and pending special assessments

Operating expenses

Maintenance

Your assumption

Share of scheduled rent

Property management

Your assumption

Share of collected income

Owner-paid utilities

Your assumption

Capex reserve

Your assumption

Roof, HVAC, appliances

Other expenses

Your assumption

Projection

Hold period

Your assumption

Appreciation

Your assumption

Per year, from purchase price

Rent growth

Your assumption

Per year

Expense growth

Your assumption

Fixed costs, per year

Selling costs at exit

Your assumption

Year 1

Returns

Monthly cash flow

-$1,225

After debt service

Cash-on-cash

-11.30%

Cap rate

2.68%

After capex reserve

DSCR

0.44

Lenders look for ≥ 1.25

Assumes 25% down, 7.25% rate, 30-yr amortizing loan, 1% points

Calculated from your assumptions

Model warnings

Critical: Negative cash flow: about −$1,225 per month in year 1.
Critical: DSCR 0.44 is below 1.25 (typical lender minimum).
Warning: Cash-on-cash return is negative.
Warning: Negative leverage: cap rate 2.7% is below the 7.2% loan rate, so borrowing reduces the return on cash.
Critical: Break-even occupancy is 134.8% — little room for vacancy.
Note: Operating expenses are 66.3% of effective income — verify tax and insurance quotes.

Income, expenses and cash

Gross scheduled income: $36,000
Vacancy & credit loss: -$2,160
Effective gross income: $33,840
Operating expenses (incl. reserve): -$22,444
Net operating income (NOI): $11,396
Annual debt service: -$26,093
Annual cash flow: -$14,697

Debt service: 25% down, 7.25% rate, 30-yr amortizing loan, 1% points

Expense detail

Property tax: $8,500
Insurance: $6,000
Maintenance & repairs: $2,160
Property management: $3,384
Capital-expenditure reserve: $1,800
Other expenses: $600

Calculated from your assumptions

Acquisition and ratios

Total cash invested: $130,063
All-in cost: $448,813
Loan amount: $318,750
Monthly principal & interest: $2,174
NOI before capex reserve: $13,196
Cap rate before reserve: 3.10%
Cap rate on all-in cost: 2.54%
Gross yield (rent ÷ price): 8.47%
Break-even occupancy: 134.8%
Operating expense ratio: 66.3%
Gross rent multiplier: 11.8

Calculated from your assumptions

Hold 10 years

Projection and exit

Sale proceeds after selling costs and loan payoff: $253,213
Total profit (cash flow + sale − cash invested): -$15,327
Equity multiple: 0.88×
IRR (pre-tax): -0.82%

Annual cash flowNegative cash flowEquity (value − loan)

Calculated from your assumptions — property value grows from the purchase price at the appreciation rate

Scenarios

Your base case next to conservative and optimistic bands (Illustrative Assumptions).

Scenario comparison
Metric	Conservative	Base case	Optimistic
Monthly cash flow (year 1)	-$1,632	-$1,225	-$926
Annual cash flow (year 1)	-$19,580	-$14,697	-$11,108
Cash-on-cash return	-14.88%	-11.30%	-8.57%
Cap rate	1.84%	2.68%	3.22%
NOI (year 1)	$7,823	$11,396	$13,701
DSCR	0.29	0.44	0.55
Break-even occupancy	148.3%	134.8%	125.4%
Total cash invested	$131,563	$130,063	$129,563
IRR over hold	-3.94%	-0.82%	1.49%
Equity multiple	0.43×	0.88×	1.21×

“—” = not defined for that scenario (e.g. no cash invested or no loan). Base financing: 25% down, 7.25% rate, 30-yr amortizing loan, 1% points; scenarios shift the rate as listed below.

Conservative: rent −5%, vacancy +3 pts, insurance +15%, property tax +5%, rate +0.5 pts, renovation +15%
Optimistic: rent +5%, vacancy −2 pts, insurance −5%, rate −0.5 pts, renovation −5%

Calculated from your assumptions — scenario bands are Illustrative Assumptions, not forecasts

Stress tests

What a single adverse move does to cash flow and debt coverage — including the South Florida risks: insurance, HOA and special assessments.

9 of 9 stress tests fail (negative cash flow or DSCR below 1.25). Assumes 25% down, 7.25% rate, 30-yr amortizing loan, 1% points.

Stress tests — one assumption changed at a time
Stress test	Annual cash flow	Cash-on-cash	DSCR	Result
Base case	-$14,697	-11.30%	0.44	Fail Cash flow below $0 · DSCR below 1.25
Rent −10%	-$17,347 −$2,650	-13.34% −2.04 pts	0.34	Fail Cash flow below $0 · DSCR below 1.25
Vacancy +5 pts	-$16,317 −$1,620	-12.55% −1.25 pts	0.37	Fail Cash flow below $0 · DSCR below 1.25
Insurance +25%	-$16,197 −$1,500	-12.45% −1.15 pts	0.38	Fail Cash flow below $0 · DSCR below 1.25
Insurance +50%	-$17,697 −$3,000	-13.61% −2.31 pts	0.32	Fail Cash flow below $0 · DSCR below 1.25
Property tax +15%	-$15,972 −$1,275	-12.28% −0.98 pts	0.39	Fail Cash flow below $0 · DSCR below 1.25
HOA / condo fees +20%	-$14,697 $0	-11.30% 0 pts	0.44	Fail Cash flow below $0 · DSCR below 1.25
Special assessment $15k (one-time)	-$14,697 $0	-10.13% +1.17 pts	0.44	Fail Cash flow below $0 · DSCR below 1.25
Interest rate +1 pt	-$17,340 −$2,643	-13.33% −2.03 pts	0.40	Fail Cash flow below $0 · DSCR below 1.25
Renovation +20%	-$14,697 $0	-11.13% +0.17 pts	0.44	Fail Cash flow below $0 · DSCR below 1.25

“—” = not defined (no loan for DSCR, no cash invested for returns). The special-assessment amount is an illustrative assumption.

Calculated from your assumptions — each row changes a single input; the others stay at the base case

Which assumptions matter most

Each input moved ±10% on its own. The longest bars are the figures worth verifying first.

Most influential assumption: Monthly rent — moving it ±10% shifts annual cash flow by up to ±$2,650.

Sensitivity of Annual cash flow to each assumption (±10%)
Assumption	Input −10%	Base	Input +10%
Monthly rent	-$17,347	-$14,697	-$12,048
Purchase price	-$12,088	-$14,697	-$17,307
Interest rate	-$12,844	-$14,697	-$16,604
Down payment	-$15,567	-$14,697	-$13,827
Property tax	-$13,847	-$14,697	-$15,547
Insurance	-$14,097	-$14,697	-$15,297
Management fee	-$14,359	-$14,697	-$15,036
Maintenance	-$14,481	-$14,697	-$14,913

Calculated from your assumptions — one input changed at a time, all others held at the base case

Acquisition

Purchase price

Your assumption

Acquisition costs

Your assumption

Title, closing — share of price

Renovation

Renovation budget

Your assumption

Contingency

Your assumption

Share of budget

FinancingFinanced

Use a short-term loan

Your assumption

Loan-to-cost

Your assumption

Of purchase + renovation budget

Interest rate (interest-only)

Your assumption

Loan points

Your assumption

Holding

Holding period

Your assumption

Purchase to sale closing

Property tax

Your assumption

Insurance (vacant / builder's risk)

Your assumption

Utilities

Your assumption

Other holding costs

Your assumption

HOA, lawn, security

Exit

After-repair value (ARV)

Your assumption

Always an estimate — base it on renovated comps

Selling costs

Your assumption

Commission + seller closing, of sale price

6-month hold

Returns

Estimated profit

$29,281

ROI on cash

27.2%

Annualized ROI

61.9%

Margin of ARV

5.6%

Many investors target ≥ 10%

Assumes 85% loan-to-cost, 11% interest-only, 2% points

Calculated from your assumptions

Model warnings

Warning: Profit margin 5.6% of ARV is below 10% — little cushion for overruns or a lower sale price.
Warning: Purchase price is above the 70%-rule maximum offer of $292,500 (a rule of thumb, not a valuation).

Cash and break-even

Cash required: $107,469
Loan amount: $344,250
Total project cost (incl. selling): $490,719
Break-even sale price: $488,345
Return on total cost: 6.0%
70% rule maximum offer (rule of thumb): $292,500

Holding and financing detail

Property tax: $3,400
Insurance: $1,800
Utilities: $1,500
Other holding (HOA, lawn, security…): $900
Loan points: $6,885
Interest (interest-only): $18,934

Calculated from your assumptions

Cost breakdown

Purchase price: $340,000
Acquisition costs: $6,800
Renovation + contingency: $71,500
Holding costs: $7,600
Financing (points + interest): $25,819
Selling costs: $39,000
Total project cost: $490,719
Estimated profit: $29,281

Calculated from your assumptions

Buy-to-rent vs fix-and-flip

Uses the current inputs from the other two tabs — edit them there.

This comparison depends entirely on the assumptions in each calculator. The two strategies differ in time horizon, risk and effort, so a higher percentage is not automatically the better choice.

Buy-to-rent versus fix-and-flip
Metric	Buy-to-rent	Fix-and-flip
Cash required Rental: down payment, closing, points, renovation. Flip: all costs before sale minus the loan.	$130,063	$107,469
Financing	25% down, 7.25% rate, 30-yr amortizing loan, 1% points	85% loan-to-cost, 11% interest-only, 2% points
Time horizon	10 years	6 months
Annual cash flow (year 1) / project profit	-$14,697	$29,281
Return on cash Rental: year-1 cash-on-cash. Flip: profit ÷ cash required (whole project).	-11.30%	27.25%
Annualized return Rental: pre-tax IRR over 10 years incl. sale. Flip: ROI compounded to 12 months.	-0.82%	61.92%
Total profit over the horizon	-$15,327	$29,281
Break-even	134.8% occupancy	$488,345 sale price

Buy-to-rent risk notes

Negative cash flow: about −$1,225 per month in year 1.
DSCR 0.44 is below 1.25 (typical lender minimum).
Break-even occupancy is 134.8% — little room for vacancy.
Rent, vacancy, insurance and tax changes compound over a multi-year hold; the sale price at exit is an assumption.

Fix-and-flip risk notes

Profit margin 5.6% of ARV is below 10% — little cushion for overruns or a lower sale price.
Purchase price is above the 70%-rule maximum offer of $292,500 (a rule of thumb, not a valuation).
Profit is concentrated in one sale: the resale price, renovation overruns and delays drive the outcome.

Calculated from your assumptions

Projections are illustrative and not guaranteed. Not investment advice. Figures are calculated from the assumptions shown; verify every input independently before making a decision.