This report examines how modern, open-source assessment methods could produce fair, transparent, and affordable countywide reassessments in Allegheny County. Using publicly available data and open-source valuation models, we estimate updated assessments for residential properties, evaluate quality against IAAO standards, and estimate implementation costs.

Findings show modern automated valuation methods produce assessments substantially closer to market value than the current system. The largest relative increases occur in neighborhoods that appreciated rapidly over the past decade, particularly within the City of Pittsburgh. Existing land assessments often value neighboring parcels differently despite identical locations, reducing confidence in fairness.

Regular reassessments could be performed in-house for approximately $1 million per year, far below court-ordered costs. Based on economics literature, regular reassessments could generate tens of millions in annual economic benefits by improving efficiency and increasing confidence. The report introduces open-source methodology for estimating total property and land values, documents dataset limitations, and demonstrates how transparency improves public confidence.

We've released an online Home Assessment Explorer allowing residents to view estimated assessments and tax impacts. Our goal is not to produce the official reassessment, but to demonstrate modern reassessment is technically feasible, affordable, and should use transparent methods and open data.