Paired Sales Analysis Calculator

Enter both sales data to see the step-by-step analysis.

The concept

Paired sales analysis finds two comparable sales that are nearly identical except for one feature. By comparing their prices (after adjusting for any remaining differences), appraisers can isolate the market's value contribution for that specific feature.

When appraisers use it

It is the gold standard for supporting adjustments in the sales comparison approach. Common uses include deriving GLA adjustments, garage adjustments, pool adjustments, bedroom count adjustments, and condition or quality adjustments. Fannie Mae guidance strongly encourages market-derived adjustments over appraiser judgment alone.

Limitations

Perfectly matched pairs are rare. Most pairs have multiple differences that must each be accounted for. Appraisers should use several pairs when possible and look for consistency in the indicated values. One pair is a data point; three to five pairs is a pattern.

What is paired sales analysis?

Paired sales analysis is an appraisal technique that compares two or more similar sales that differ in one specific characteristic. By controlling for all other variables, the price difference can be attributed to the feature being measured, providing a market-supported adjustment amount.

How many pairs do I need?

More is better. One pair provides a single data point that could reflect unique buyer/seller motivations. Three or more consistent pairs provide a reliable range. When paired data is scarce, appraisers supplement with other methods like statistical analysis, cost-to-cure, or percentage-based adjustments.

Can I use this to calculate a GLA adjustment rate?

Yes, that's one of the most common uses. Find two comparable sales that differ primarily in GLA (same neighborhood, condition, quality, features), calculate the price difference, and divide by the GLA difference to get $/sqft. Run this on multiple pairs to find a consistent rate for your market.