Comps are updated as sales occur. An appraiser working for a lender will usually choose properties within ONE mile of the subject property which sold within the last 6 months to make the comparisons. If comps are difficult to find within those parameters, TIME and DATE of sale will be expanded - but LOCATION should not be.
Beware estimates of value of sites like Zillow - they go FIVE miles to calculate their numbers which punishes the preferred areas and rewards the less desirable. They also do not take view, waterfront location or other valuable property features into consideration.... more