Most underwriting uses the seller's tax bill.That bill dies at closing.
Assessed values for recently-sold Cook County properties consistently move toward the sale price by the next reassessment. PencilOut models that shift as a first-class input — so the year-two operating picture in your memo reflects it, not the bill that's about to go stale.
Sample underwrite for a representative Chicago 3-flat, run through the same deterministic engine as every live analysis — not a live listing.
The reassessment is the deal.
A Cook County rental that pencils on the seller's bill can stop penciling the moment the assessor catches up to the sale price. Tools that carry the current bill forward aren't conservative — they're wrong in one direction, every time.
Live today for Cook County, Illinois (Chicago and suburbs). Collar-county coverage (DuPage, Will, Lake, Kane, McHenry) is planned separately, on a different model — see why.
Read the full reassessment guide →Reassessment, not the seller's bill
Assessed values for recently-sold Cook County properties consistently move toward the transaction price by the next reassessment. PencilOut models that shift on the schedule it typically lands on.
Every input is visible and adjustable
Each factor in the Deal Score is listed with its weight. Change an assumption and the score recomputes in front of you — nothing is hidden behind a model.
Confidence is rated separately
A score answers “how good.” A confidence rating answers “how much do we know.” Conflating them is how bad deals look clean.
A verdict you can argue with.
Buy, Consider, and Pass are the only colors PencilOut uses to render a verdict — we don't dress every metric in red or green and call it insight. Behind each one is a weighted list you can open, adjust, and defend in an investment-committee memo — plus a confidence rating that stays separate from the score itself.
One engine. Six ways to underwrite a Chicago deal.
Single-family house hack to a 40-unit commercial refinance. Buy-and-hold to a six-month flip. Each strategy gets its own purpose-built scorecard — not the long-term-rental math wearing a different label.
Long-term rental
Cash flow, cap rate, cash-on-cash, and DSCR — the core rental underwrite, reassessment included.
Short-term rental
Nightly-rate and occupancy revenue modeling, plus a legality-confirmation disclosure before it scores.
House hack
Owner-occupied-unit economics, homestead-exemption tax modeling, and a net-savings-vs-renting comparison.
BRRRR
Scores the deal you're actually holding post-refinance, with an as-purchased-vs-post-refi disclosure — never a silent swap.
Flip
A different scorecard entirely: profit margin, ROI-on-cash, ARV confidence, market liquidity, rehab-budget risk.
DSCR (5–49 unit)
Commercial DSCR/LTV loan-sizing math with a hard-constraint qualification callout, built on real Chicago lender terms.
Teams that have to show their work.
Investment firms
Screen deal flow at volume and hand the committee a memo page that shows its work.
Family offices
Hold-period assumptions you control, documented line by line, with no black-box verdict.
Brokerage teams
Send buy-side clients an underwrite that survives their analyst's second look.
Underwrite the year-two bill, not the year-zero one.
Create an account and underwrite your first Chicago deal today.
No credit card. The demo runs a sample property — no sign-up needed.