There are not many realtors licensed to do appraisals
It is just a matter of getting comparables.
Most agents can get comparables as they use that information when they put a home up for sale to determine the asking price
Brokers have the most experience/education
The larger firms have appraisers they call when needed
Your home owners insurance company should have contact to an appraiser to evaluate the value of one's home for insurance purposes
A bank that offers home mortgages should have contact to one to determine if a home is of equal or greater value for a mortgage