Online Course 805: Mass Appraisal of Residential Property. Mass appraisal is the systematic appraisal of grouped properties using standardized procedures and statistical testing. The course covers the statistical analysis of measures of central tendency and measures of dispersion as they relate to assessment uniformity. Methods and techniques of mass appraisal are applied through intensive case problem work. The recommended prerequisites for this course are Site Analysis and Evaluation, An Introduction to the Cost Approach to Value, An Introduction to the Sales Comparison Approach to Value, or IAAO Course 101, or the equivalent. Purchasing this course will allow 180 days access starting from the date of purchase. Only the person purchasing the course will be allowed access. You will receive an email after purchase with a link to the course. You may also access the course through "My Account". It is worth 10 hours of continuing education credit.