I looked up some data for that area, and based on what I’m seeing I wouldn’t trust the Zillow estimate to be that accurate. A lot of homes in that size range have much larger sites than you have and are sited along that ridgeline to offer some views.
Zillow will work better for homes that are part of of large subdivisions that are built by the same developer. Tract homes. The less homogenous a neighborhood is the less accurate an automated valuation model like Zillow can be. Zillow basically can’t account for site attributes (including noise, view, topography, etc), nor can it account for additional improvements to the site or the home. For instance, a home might have originally been built in 1980, but if it was completely remodeled and updated to resemble a 1990s home those would usually be the more appropriate comparables.
From what I’m seeing you may have sold a year early but I wouldn’t assume the $600,000 figure is anywhere near accurate. The real number could be less than half that.
The other thing that everyone should remember is that Piggington’s is San Diego-centric. San Diego’s dynamic runs on a different clock than the L.A and O.C. markets. Those areas have only recently joined in with our trend.