You're scrolling through listings. You find a property. On paper, it looks good. The price is reasonable. The area is solid.

Now what?

If you start pulling full financial projections, underwriting, and analysis, you'll spend four hours on a deal that's probably not going to work anyway. Most deals fail on one of four tests: gross rent multiplier, DSCR, stress test, or cash-on-cash return. The 15-minute framework helps you identify which one kills each deal so you can move fast to properties that actually work.

That's why I use a 15-minute framework.

In 15 minutes, you'll know: (1) is this worth looking at further, or (2) pass and move to the next one.

The discipline is in saying no fast.

What's Your Actual 15-Minute Rental Property Analysis Process?

I'm going to walk through a real example step by step. You'll time yourself. You'll know the framework.

The Property:

4-unit building, Beacon Hill
List price: $850K
Built: 1990
Condition: good
Renter-occupied: all four units

Let's go.

Minute 0–2: Collect the Data Points (Data Gathering)

Open the MLS listing. You need three things:

Purchase price: $850K
Estimated rent per unit (from comparable listings or rent comps)
Property taxes (visible in MLS, Zillow, or county assessor)

For this property:

Purchase price: $850K
Comparable rent (4-unit building, Beacon Hill): $1,900/month per unit
Annual gross rent: $1,900 × 4 × 12 = $91.2K
Property taxes (estimated): $10.2K/year

Done in two minutes. Move on.

Minute 2–4: Calculate Gross Rent Multiplier (The First Filter)

GRM = Purchase Price / Annual Gross Rent

GRM = $850K / $91.2K = 9.3x

What's a good GRM?

Under 12: strong (you're paying less per $1 of rent)
12–15: workable
15–20: expensive (rents are low relative to price)
Over 20: probably overpriced

This property at 9.3x is strong. It passes the first filter. The GRM framework pairs with detailed multifamily analysis when you're narrowing down between actual deals.

That was two minutes. You've eliminated 70% of the bad deals already.

Minute 4–6: Estimate Operating Expenses (The 50% Rule)

Operating expenses typically run 30–50% of gross rent depending on property type and age.

For quick analysis, use the 50% rule: assume operating expenses are 50% of gross rent. This includes property taxes, insurance, maintenance, utilities, and property management.

If gross rent is $91.2K, operating expenses = $91.2K × 0.50 = $45.6K

Adjusted Gross Income (AGI): $91.2K − $45.6K = $45.6K

You now have an estimate of Net Operating Income (NOI) for analysis purposes.

Note: The 50% rule is conservative. For a newer building, expenses might be 35–45%. For a 50-year-old building, 55%+. Use 50% as your baseline for new deals.

Minute 6–8: Run a Quick DSCR (Debt Service Coverage Ratio)

This is the lender's test. Your NOI must be at least 1.20x your annual debt service.

Assume a typical loan structure for this property:

Loan amount: $680K (80% LTV)
Interest rate: 5.5% (current market)
Term: 30 years
Annual debt service: ~$40.8K (you can use an online calculator for 30 seconds)

DSCR = NOI / Debt Service = $45.6K / $40.8K = 1.12x

That's below the 1.20x lender requirement.

Red flag.

Lenders won't touch this. You'd need 70% LTV instead of 80% to hit 1.20x DSCR.

But wait. The 50% rule is conservative. If actual operating expenses are 45% instead of 50%, your NOI is $50.16K, and DSCR becomes 1.23x. That works.

So your question becomes: can you verify operating expenses?

Two minutes in, you've found the key question.

Minute 8–10: Stress Test (What If?)

Don't move forward without stress testing.

Scenario 1: What if rents are 5% lower than your comp?

Gross rent: $91.2K × 0.95 = $86.64K
Operating expenses (50%): $43.32K
NOI: $43.32K
DSCR: $43.32K / $40.8K = 1.06x ← Fails lender requirement

Scenario 2: What if operating expenses are actually 55%?

Gross rent: $91.2K
Operating expenses (55%): $50.16K
NOI: $41.04K
DSCR: $41.04K / $40.8K = 1.01x ← Barely alive

Scenario 3: What if rates stay at 5.5% or go up?

Your debt service doesn't change, but future refinancing gets more expensive
This property has little cushion for rate changes

Result: this property is marginal. It passes GRM, but the DSCR is tight, and stress tests show it's vulnerable to rent softness or expense increases.

Decision: Pass or investigate further?

At 15-minute mark, I'd say: investigate further IF you can:

Get actual operating expenses from the current owner
Verify rents are truly achievable in Beacon Hill
Find a lender willing to do 70% LTV instead of 80% (lower loan amount, easier DSCR)

Otherwise: pass and find the next deal.

Minute 10–15: Calculate Cash-on-Cash Return (For Deals That Pass)

If a property passes GRM and DSCR, calculate cash-on-cash to see if it's worth your capital. This is where leverage really matters—the difference between buying with 20% down vs. 60% down shows up here, not in cap rate.

Using 70% LTV (to hit DSCR):

Loan: $595K
Down payment: $255K
Closing costs (2%): $17K
Total capital: $272K

Annual cash flow (if you buy at 70% LTV):

NOI: $45.6K (using 50% rule)
Debt service ($595K at 5.5%, 30 years): $35.7K
Annual cash flow: $9.9K

Cash-on-cash return: $9.9K / $272K = 3.6%

That's weak. Less than 6% doesn't meet most investors' threshold.

Final verdict: Pass. Even if this property passes GRM and DSCR, the cash-on-cash return is too low. You'd be paying $272K to make $9.9K annually. That's 3.6% on your capital with all the landlord headaches. If you want to understand the framework for DSCR loans and non-owner-occupied financing, that's a separate conversation, but this deal still doesn't work.

Find a deal that generates 8%+ cash-on-cash.

Real Example 2 (The One That Works)

Let me run the same analysis on a property that does work.

The Property:

3-unit building, Everett
List price: $525K
Built: 1995
Condition: good
All three units rented

Step 1: GRM

Purchase price: $525K
Comparable rent (3-unit, Everett): $1,400/month per unit
Annual gross rent: $1,400 × 3 × 12 = $50.4K
GRM: $525K / $50.4K = 10.4x ← Strong, passes

Step 2: Operating Expenses

Gross rent: $50.4K
Operating expenses (50%): $25.2K
NOI: $25.2K

Step 3: DSCR

Loan (75% LTV): $393.75K
Annual debt service: $23.6K
DSCR: $25.2K / $23.6K = 1.07x ← Below 1.20x, but close

Hmm, marginal again. Let's stress test.

Step 4: Stress Test

Scenario: Expenses are actually 45% instead of 50%

Operating expenses: $22.68K
NOI: $27.72K
DSCR: 1.17x ← Still a bit low, but closer

Scenario: You buy at 70% LTV instead

Loan: $367.5K
Debt service: $22K
DSCR: $25.2K / $22K = 1.15x ← Getting there

Decision: This property is workable if you can:

Verify operating expenses are closer to 45% than 50%
Buy with 70% leverage
Find actual rents in the market (don't just use estimates)

Step 5: Cash-on-Cash (70% LTV scenario)

Loan: $367.5K
Down payment: $157.5K
Closing costs: $10.5K
Total capital: $168K

Annual cash flow (70% LTV):

NOI: $25.2K
Debt service: $22K
Annual cash flow: $3.2K ← Tight

Cash-on-cash return: $3.2K / $168K = 1.9% ← Too low

Wait, this deal doesn't work either.

The lesson: just because a property passes GRM and DSCR doesn't mean it's profitable for you.

The Pattern (Why Most Deals Don't Work)

In King County, most 3–4 unit buildings are trading at GRM ratios that don't generate strong cash flow.

Rents haven't caught up to prices in appreciating neighborhoods. You're buying for appreciation, not income.

That's fine if you can:

Afford to hold and wait for appreciation (5+ years)
Absorb negative or minimal cash flow
Have other income to cover the gap

If you need monthly cash flow, you either need to:

Find a deal in an emerging neighborhood (lower price, higher rents relative to price)
Negotiate a lower purchase price
Find a property with below-market rents (value-add play)

How Do You Know If a Deal Actually Works After the 15-Minute Test?

Use this exact checklist:

[ ] GRM under 12 → If not, next deal [ ] Estimated NOI passes DSCR at 75% LTV → If not, stress test hard [ ] Stress test passes at reasonable assumptions → If not, next deal [ ] Cash-on-cash return is 8%+ → If not, next deal [ ] Or: deal is in appreciation-heavy market and you can afford the wait → If yes, investigate

Most deals fail at step 3 or 4. That's normal. That's healthy.

The goal isn't to find a perfect deal. The goal is to eliminate bad deals in 15 minutes so you can spend deep analysis time on the few that might work.

Have a deal you want me to look at?

Common Mistakes in the 15-Minute Analysis

Mistake 1: Using list price as the offer price

List price is usually negotiable. Use it as a starting point, but assume you can negotiate 2–5% lower.

If a deal barely works at list price, it's not really a deal.

Mistake 2: Overestimating rents

Check at least three comparable properties actively listed for rent in the market. Call landlords. Ask what they're actually charging, not what they'd like to charge.

Overestimate rents, and your numbers are fiction.

Mistake 3: Using the 50% rule for below-market properties

If a building has been owner-managed or has deferred maintenance, expenses could be 60%+ of gross rent.

Get actual numbers if you suspect this.

Mistake 4: Ignoring the cap rate entirely

Cap rate is NOI / purchase price. Calculate it as a sanity check.

If cap rate is below 4%, you're betting entirely on appreciation. There's nothing wrong with that, but know what you're buying.

Mistake 5: Forgetting to stress test

A property that works at perfect assumptions is a unicorn. Always ask: what happens if rents drop 5%? What if expenses jump 10%? What if rates stay at 5.5%+?

If it survives stress, it's a real deal.

When to Spend More Than 15 Minutes

Once a property passes the 15-minute screen, do deeper work:

Get actual rent rolls and leases from the seller
Walk the property and estimate maintenance needs
Talk to the property manager about actual operating expenses
Pull actual rent comps from multiple sources
Run the numbers with a loan officer to confirm terms
Have a property inspector evaluate condition

Deep analysis might take 4–8 hours. But you're only doing that for deals that already passed the first filter.

Real Talk: Most Deals Are a Pass

I've analyzed hundreds of properties. Probably 80% fail the 15-minute test.

Of the 20% that pass, probably 50% of those fail deeper analysis.

So roughly 10% of properties I look at make it to an actual offer.

And of those, maybe 70% close.

That means from 100 properties I review, maybe 7 actually close.

That's normal. That's healthy. The discipline to say no fast is what separates successful investors from people who waste time on bad deals.

Use this framework. Eliminate mercilessly. Move fast on the deals that work.

The 15-Minute Checklist (Copy & Paste Version)

Save this. Use it every time:

[ ] Purchase price: $_______ [ ] Annual gross rent: $_______ [ ] GRM: _________ (under 12 = pass) [ ] Operating expenses (50% rule): $_______ [ ] NOI: $_______ [ ] DSCR at 75% LTV: _________ (need 1.20x+) [ ] Stress test: can it survive at -5% rents? Y/N [ ] Cash-on-cash return: _________ (need 8%+) [ ] Decision: [ ] Investigate Further [ ] Pass

Take 15 minutes. Fill it out. Move on.