Kill It Fast or Underwrite It Fully: A Two-Stage Screening Workflow for Triaging 20 Flip Leads a Week

Why Every Lead Doesn't Deserve a Full Underwrite

A full underwrite in a spreadsheet usually takes 60 to 90 minutes. You pull comps, adjust them for size and condition, build a rehab budget line by line, and then layer in closing, holding, and selling costs. Multiply 75 minutes by 20 leads and you've spent 25 hours a week, mostly on deals you were going to reject anyway. The fix is a two-stage funnel that spends your time only where the odds justify it.

Stage 1 is a kill screen. You use a ballpark ARV from a few nearby sales, a rehab band priced per square foot (for example, $25 for light cosmetic, $45 for medium, $70 or more for heavy), and the quick formula MAO = (ARV x 0.70) - rehab. Take a 1,400 sq ft house with a rough ARV of $240,000 and a medium rehab of $45 x 1,400 = $63,000. That gives $168,000 - $63,000 = $105,000. If the seller wants $165,000, the lead dies in about five minutes. The goal here is a fast no, not a precise yes.

Stage 2 is the full underwrite, and only survivors get it. Adjusted comps within half a mile replace the ballpark ARV. A line-item rehab by trade replaces the per-foot band. Real buying, holding, and selling costs plus your target profit replace the 70% shortcut. This is the number you actually put in an offer.

Some of this work is pure mechanics and worth automating: comp pulls, county-priced rehab lines, and the MAO arithmetic. A tool like FlipSmrt handles those in under five minutes per address, so the time-consuming parts of both stages shrink.

Other calls still need you. Set your kill threshold, such as "asking more than 15% above MAO gets cut." Read condition clues in photos and remarks, like "as-is," "cash only," or a fresh coat of paint over a cracked foundation wall. Weigh seller motivation too, because a probate estate asking 20% over MAO may negotiate where a retail seller won't.

Worked Example: Screening 20 Leads Down to 6 in One Sitting

Stage 1 runs on one rule, written down before you open the first lead: kill any lead where the asking price is more than 15% above the screen MAO. The screen MAO uses rough inputs only. That means a quick ARV from a handful of nearby sales and a ballpark rehab based on condition and square footage, plugged into (ARV x 0.70) minus rehab. Give each lead two or three minutes, then move on.

Here's a lead that dies. The seller is asking $245,000. Your rough ARV is $300,000 and your rough rehab is $40,000, so the screen MAO is $210,000 minus $40,000, or $170,000. The asking price is $75,000 over that, which works out to about 44% above. You would need the seller to drop almost a third of their price just to reach the edge of your buy box, so it's a kill with no second look.

Here's one that survives. Asking is $189,000, rough ARV is $320,000, and rough rehab is $45,000. The screen MAO is $224,000 minus $45,000, or $179,000. Asking sits $10,000 above that, roughly 6%, which falls well inside the 15% band (your ceiling is about $205,850). That gap is a normal negotiation, so this lead advances to Stage 2.

Run all 20 leads through the same rule and the list shrinks fast. In this hypothetical batch, 9 leads come in more than 30% above screen MAO. Another 5 land between 16% and 29% above. That's 14 kills and 6 survivors, and the whole pass takes roughly an hour.

The 15% buffer is deliberately loose. Your rough ARV might be light by $10,000 to $20,000, sellers often take less than asking, and a rough rehab guess can swing either way. A loose screen means a few weak deals reach Stage 2, where the full underwrite kills them properly. That's a better trade than a tight screen that quietly throws away the one real deal in the stack.

Worked Example: Full Underwrite on the Survivor

One of the six survivors is a 3-bed, 2-bath ranch listed at $189,000. It passed the kill screen, so now it gets the real treatment. Stage 2 replaces rough guesses with defensible numbers for every cost bucket. The goal is a Maximum Allowable Offer you would actually sign.

Start with value. Sold comps within 0.5 miles, adjusted for square footage, bed and bath count, and condition, put the ARV at $312,000. Next comes cost. A line-item rehab by trade (roof, kitchen, flooring, HVAC service, paint) priced for the county totals $51,800. Then layer in the costs a quick screen ignores:

• Buying costs: $3,500
• Holding: 5 months at $2,100 per month = $10,500
• Selling costs: 7% of $312,000 = $21,840
• Target profit: $35,000

Now the arithmetic: $312,000 - $51,800 - $3,500 - $10,500 - $21,840 - $35,000 = $189,360. The asking price is $189,000, so the deal works at list with $360 of headroom. That is thin, but it is a real yes, and you know exactly which line items to protect. If rehab creeps by $5,000, you need a lower offer or a lower profit target.

Compare that to the 70% rule: ($312,000 x 0.70) - $51,800 = $218,400 - $51,800 = $166,600. That number sits $22,400 below asking, and it would have pushed you to lowball or walk. The shortcut builds in a generic cushion. The full underwrite shows this deal's actual costs, and here those costs leave room the rule does not see. Neither number is wrong. The full version is simply the one built on this specific property.

Built by hand, this underwrite takes about an hour of pulling comps, adjusting them, and pricing trades in a spreadsheet. Multiply that by six survivors and Stage 2 eats your whole week. FlipSmrt returns the same adjusted ARV, county-priced rehab, MAO, and ROI with a plain-English verdict in under 5 minutes. At that speed, every survivor gets a full underwrite instead of a gut call.

Edge Cases That Break a Simple Kill Screen

A kill screen trades precision for speed, so it will sometimes kill a lead that later becomes a deal. The most common cause is a price cut. Say a listing asks $199,000, your ballpark ARV is $300,000, and rehab looks like $45,000. Your screen MAO is $165,000 ($300,000 x 0.70 = $210,000, minus $45,000), so the lead dies today. If the seller drops to $179,000 after 60 days, the gap shrinks to $14,000, which is negotiable. Keep every killed lead priced within 25% of your MAO on a watchlist, and re-screen it whenever the price changes.

False positives usually hide in the listing photos. A cheap price per square foot lets a lead through, but the photos show fresh paint and nothing else. Watch for these flags:

• No photos of the basement, roof, or mechanicals
• "As-is," "cash only," or "investor special" in the remarks
• A pre-1960 build with no mention of updates

If a lead shows two or more flags, add $25,000 to your rehab guess before it advances. That buffer roughly covers one hidden roof or foundation problem.

Thin-comp areas break the screen from the other side. If you can't find at least three sold comps within half a mile from the last six months, your ballpark ARV is a guess. A $20,000 ARV miss moves your MAO by $14,000 at 70%, which is enough to flip a pass into a kill. Rural streets and blocks with mixed housing stock are the usual culprits.

Price bands matter too. On a $600,000 ARV, a 30% margin is $180,000, more than most flips need, so 75% to 80% is often fairer. On a $90,000 ARV, 30% is only $27,000. Selling costs (about $7,200 at 8%) and $8,000 of buying and holding costs leave roughly $11,800 of profit, so tighten to 65%.

Skip Stage 1 entirely when the screen's verdict depends on a number you can't trust. That means thin comps, two or more photo flags, or an asking price within 10% of your screen MAO. Send those leads straight to a full underwrite.

Common Mistakes When Running a Screening Funnel

The most expensive mistake is a kill threshold so tight that real deals die in Stage 1. Say a lead has a rough ARV of $280,000 and a ballpark rehab of $50,000. Your quick MAO is ($280,000 x 0.70) - $50,000 = $146,000. If you kill everything asking above $146,000, a house listed at $155,000 never gets a second look, even though sellers rarely get their asking price. A buffer works better: kill only when the ask is more than 15% over your rough MAO, which here means $146,000 x 1.15 = $167,900.

The second mistake runs the other way: treating a Stage 1 number as an offer. Stage 1 runs on a rough cost per square foot and a quick ARV guess. It tells you whether a lead deserves an hour of your time, not what to pay. Offer off that number and you either overpay or retract after a walkthrough, and agents remember investors who retract.

Stage 2 has its own traps. Zestimate-style automated values blend renovated and dated sales, so they can drift well away from a true after-repair value. Pull real sold comps within half a mile, then adjust for condition, beds, baths and square footage. Also cap the time you spend. If one underwrite stretches into a three-day spreadsheet project, the deal is often gone before you finish. Give each Stage 2 lead a fixed window. A tool like FlipSmrt returns adjusted comps, county-priced line-item rehab and an MAO in under 5 minutes, which keeps you inside that window.

Finally, killed leads are not dead forever, and kill reasons are data. Keep a simple log with the address, asking price, rough MAO and the reason it died: price, rehab scope, weak comps or location. Check price-drop alerts on those addresses weekly, because a $20,000 cut can push a lead back over the line. After a month, review the log. If most kills cite price and you close nothing, your threshold is probably too tight. If you underwrite plenty of leads that later fail on rehab, your Stage 1 cost estimate is too generous.

FAQ: Deal Triage and Screening Workflows

How loose should my kill threshold be, and how many leads should survive?

Set Stage 1 loose enough that you never kill a deal you might have bought. A practical rule is to keep any lead priced within 10% of your quick MAO. If a rough ARV is $300,000 and rehab looks like $45,000, your quick MAO is ($300,000 x 0.70) - $45,000 = $165,000, so anything asking up to about $181,500 survives. Expect roughly 20% to 35% of leads to pass. If 10 of 20 survive, tighten the threshold. If only 1 or 2 survive, loosen it.

Can I skip Stage 1 if I use an AI analysis tool?

You can, but you probably shouldn't. A full FlipSmrt analysis takes a few minutes per property, so running all 20 leads costs more than an hour that a 30-second napkin screen would save. Use the quick screen to drop the obvious no's, then run the survivors through the full analysis for adjusted comps, county-priced rehab, and a real MAO. Your first 3 FlipSmrt analyses are free, which is enough to test the Stage 2 step on this week's best leads.

What do I do with a lead that lands right at MAO, like the $189,000 example?

A deal at exactly MAO has no cushion above your target profit. Every dollar of rehab overrun comes straight out of your profit, so a $7,000 surprise in the electrical panel costs you $7,000 of profit. Re-check the two inputs most likely to be wrong, the comps and the rehab scope. If both hold up, offer a few thousand under MAO to build margin, and be ready to walk if the seller won't move.

How often should I re-screen my watchlist?

Re-screen weekly, on the same day you run new leads. Re-run any watchlist property when the price drops 5% or more, or when it passes 60 days on market and the seller may be more flexible. A deal that failed at $210,000 can pencil at $189,000, so don't throw out near misses.