How Parclio Works
Our data sources, model logic, confidence levels, and limitations
1. What Parclio Does
Parclio is a deterministic rules engine, not an AI that generates or invents estimates. When you enter deal inputs, Parclio looks up the published reassessment rules for that jurisdiction and applies them to your inputs. There is no probabilistic inference or machine-generated approximation involved in the core tax estimate.
The rules for each county encode the specific factors that drive reassessment: assessment ratios, equalization factors, applicable millage rates, transaction trigger logic (e.g., change in ownership vs. refinance vs. entity transfer), and jurisdiction-specific exceptions. The model applies those rules to your deal inputs — purchase price, current tax bill, NOI, loan amount, and transaction type — and returns a post-closing tax estimate along with its NOI, DSCR, and debt yield impact.
2. Data Sources
All county rules are sourced from publicly available official materials. We do not rely on crowdsourced estimates or industry hearsay. For each jurisdiction, we reference at least one of the following:
- County assessor official websites and published guidance
- State department of revenue or department of taxation publications
- State board of equalization rules and annual factor tables
- Publicly available statutes and administrative code (e.g., CA Revenue & Taxation Code § 60–69 for Prop 13 change-in-ownership rules; NY Real Property Tax Law § 306 for reassessment cycles)
- Published county-level effective millage rates and levy data
Each rule entry in Parclio includes the source URL and the date it was last verified by our team. The last verified date is displayed in the County Intel panel next to the confidence level.
3. Confidence Levels
Every Parclio county entry carries a confidence score that reflects the quality and specificity of the underlying data. This is not an AI-generated confidence score — it is a human-assigned rating based on source quality.
The reassessment rule is sourced directly from official statute, administrative code, or published assessor guidance. The millage or effective rate used is from the county's own published levy data for the current or most recent tax year. This is the highest confidence level.
The reassessment rule is well-established and clearly documented. The rate used is a reliable county-level estimate, but may not reflect the exact parcel-level rate. Suitable for underwriting; confirm the specific parcel rate for precision.
The direction and trigger logic of the rule is clear, but the specific effective rate uses a county-level placeholder or a rate extrapolated from comparable jurisdictions. Use for preliminary sizing; verify the parcel's exact rate before closing.
Insufficient publicly available data, conflicting sources, or complex jurisdiction-specific factors that are not reliably captured in a general rule. Do not underwrite based on this estimate without direct confirmation from the local assessor or a qualified property tax consultant.
4. What the Model Calculates
Given your deal inputs and the applicable county rules, Parclio calculates:
5. What the Model Does Not Calculate
Parclio is designed for straightforward acquisitions and refinances of multifamily and commercial properties. The following scenarios are outside the scope of the current model:
Parclio applies the county model to the available inputs. In transaction-triggered systems, purchase price may proxy for market value. In annual-market systems, acquisition and ownership treatment varies by jurisdiction. Confirm the county rules, parcel's assessed value, valuation date, and protest status.
Mello-Roos bonds, municipal utility district (MUD) charges, and other special assessments are not included in the base estimate. Where known, these are flagged in the multifamily underwriting note.
Homestead exemptions, LIHTC qualified allocation plan exemptions, nonprofit property tax exemptions, and veterans' exemptions are not modeled. These can materially reduce the actual tax bill.
Payment-in-lieu-of-taxes agreements and negotiated abatements are property-specific and require direct confirmation with the municipality.
If the current tax bill is the subject of a pending or recently settled appeal, the estimated delta may be misleading. Confirm current bill status before using it as a baseline.
Whether a given entity transfer, assignment of beneficial interest, or change in controlling interest triggers reassessment is highly fact-specific and jurisdiction-dependent. Parclio's transfer_note field surfaces the general rule, but entity-level transactions require legal review.
6. Coverage and Update Cadence
Parclio covers jurisdictions across the highest-volume multifamily acquisition and refinance markets in the US, and coverage is expanding monthly. The Guides section shows the current list of covered states and counties.
County rules are reviewed periodically by our team. The specific cadence varies by jurisdiction — high-activity markets are reviewed more frequently. The last_verified date on each county entry indicates when the rule was last confirmed against official sources.
Tax rules change. Equalization factors, levy rates, and statute interpretations are updated by counties and state agencies on an ongoing basis. For time-sensitive transactions or counties with older verification dates, confirm current rules with the relevant assessor or a qualified property tax consultant.
7. Deal Analyzer: reading documents vs. calculating
Deal Analyzer lets you upload underwriting documents — tax bills, T12s and operating statements, rent rolls, and offering memoranda — and pulls the key figures out of them so you don't have to retype them. It is important to understand the division of labor between the AI that reads documents and the deterministic model that calculates tax reset outputs:
An AI model (Claude, from Anthropic) reads the text of your uploaded document and proposes structured values — assessed value, millage, NOI, unit count, asking price, and so on. This step is AI-assisted extraction. It is convenient but imperfect: it can miss a figure, misread a number, or infer a field from context.
Extracted values are shown to you as editable fields, clearly marked as extracted (and flagged when confidence is low or a value was inferred rather than printed). Nothing an AI extracts is treated as final. You correct anything wrong and explicitly confirm the values you want to rely on.
Only your confirmed values feed the deterministic tax reset model described above — the same rules engine used by the estimator. Tax reset outputs (post-reset tax bill, NOI impact, DSCR and debt yield impact, memo language) are calculated by that model, not generated by the AI.
Raw AI extraction is a starting point for data entry, not a finished underwriting result. Do not treat unconfirmed extracted figures as Parclio's analysis. The analysis is what the deterministic model produces from the values you have reviewed and confirmed.
8. Ask Parclio
Ask Parclio is an AI assistant (powered by Claude, from Anthropic) that interprets your deal in the context of Parclio's county rules and your estimator output. It can explain what a tax reset means for your specific deal, walk through the rule logic, identify exceptions to watch for, and help draft underwriting memo language.
A critical constraint, by design:
Ask Parclio does not invent, generate, or recompute financial figures. All tax estimates, NOI numbers, DSCR calculations, debt yield figures, and other underwriting outputs are produced exclusively by Parclio's deterministic model. The AI explains and contextualizes those outputs; it does not override or supplement them with its own calculations. If you ask the AI for a number that the model hasn't computed, it will tell you to run the estimator rather than produce a figure from its own inference.
9. Limitations and When to Consult an Expert
Parclio is a tool for professional underwriters, lenders, and brokers. It is designed to give you a fast, defensible starting point — not to replace legal or tax counsel. Always consult a local attorney, a state-licensed property tax consultant, or the relevant county assessor when any of the following apply:
- The transaction involves an entity-level transfer, assignment of a beneficial interest in an LLC, trust, or partnership, or a change in controlling interest.
- The property has a PILOT agreement, tax abatement, or negotiated assessment.
- The property is a LIHTC-qualified project, an affordable housing development with use restrictions, or a tax-exempt nonprofit property.
- The Parclio estimate shows a confidence level of “Needs review.”
- The county's next scheduled reassessment date is within 6 months of your projected closing.
- The transaction is in a jurisdiction not yet covered by Parclio.
- The current tax bill is under appeal or has been recently renegotiated.
- The property has known special assessments, MUD charges, or overlay district taxes.
Last updated: July 2, 2026