Neither. The best way to get an estimate of the market value of a home is ask a Realtor. There are many services that create estimated values of real estate, and I can assure you no two are ever the same. They are all just looking at previous sales numbers and data. They’re comparing price per square foot of recent sales, but that’s not what Realtors do. None of those estimators are able to look at the condition of the property. None of them know subtleties of the market, and none of them really look beyond the basic information to estimate the value. It takes a great deal of time and effort to accurately estimate the market value of a property, and it certainly takes more than any algorithm can produce.