This is easy to find out! Send me the address of the property and I can check for you? I would not always trust the information you see on sites like zillow, redfin etc... as they are not always updated and or complete. I can provide the full updated details for you.
For that address specifically: I think you may have the wrong address, I can't even find tax records for 107 Blackstone.
Marin Real Estate Broker
If its fairly recent sale you should be able ot look it up on Trulia which should be accurate. Agreed Zillows can tell what it sold for if you can find it. sold on MLS, but their Zestimates are quite often inaccurate/ outdated.
If you want an estimate of what a property or your house is worth, I live in San Rafael and can help get the correct info or comps for you, try my website.
Hope this helps.
T415 298 2485
The Marie Souza Team - Top Selling on Cape Cod
Cape Cod Real Estate Services