Well Renee, what we have here is a failure to communicate.
Every organization that publishes a number labeled as 'market value' is using their distinct lexicon.
Then you come along with the lexicon of the citizen believing that all things labeled 'market value' must be related. THEY ARE NOT. Yes, I know, it looks like a duck, it quacks like a duck however, in this situation...IT IS NOT DUCK!
AND, if you invest the time to read the waterfall of words all of these sites provide that explain the process of these calculations, you can walk away with the idea the poor tax paying citizen is being abused by EVERYONE.They are all basicy random number generators.
Now, let's not leave out Trulia and Zilllow who also spew out meaningless numbers that quack sounding like Market Value..
What you need to do is determine the purpose for which you intend to use those numbers.
Are you needing 'market value' in order to price your home accurately for sale? You need to call someone who helps buy and sell dozens of homes every year. Your local Remax REALTOR. Ok, you can also write a check for about $300 and have an appraiser complete an analysis. The appraiser will need to know the purpose for the appraisal. Purpose....it keeps popping up.
Perhaps ;the purpose is you are want to BUY a house and need to know the market value.
YOu will also find beneficial knowing the obstacles that will pop up in the process of buying this real estate.
Beneficial Knowing if your financing is compatible with this real estate.
If your lender will make your offer less competitive. (BofA, Wells Fargo, Chase)
Will the seller become over burdened with the complexity related to your offer.
Perhaps you would like to get a 'Clear-to-Close' financing commitment BEFORE you spend money on having a home inspected and paying the bank for an appraisal.
Or, perhaps you qualify for purchase options that allow you to save nearly 40% of the purchase price.
All of these issues are covered and addressed by your local REALTOR.
Rather than chase the make believe number you see, call a professional and get yourself equipped with REAL numbers related to your real estate.
If I was speaking with you directly, I would ask you questions about the property and it's location and then research the property to insure the accuracy of my answer(s).
Based on my understanding of your question regarding the difference in school and "town/county" "valuation" of the property the answer could be anyone of the following: (1) different governing authorities (2) possible re-assessment by one or the other authorities (3) Clerical error on records or something else altogether.
The Star exemption is a credit/reduction of the school tax bill if and only if the home owner meets ALL the criteria and not every home owner is entitled to a Star Exemption. Specifically, there are income limitations. The amount of the Star Exemption is based individual home owner criteria and not every owner gets the same percentage exemption. Generally speaking 20% is the maximum exemption amount given. In many instances, the amount is lower.
You might want to check out my website http://GeorgeC21.com where you can search all the properties for sale in the Greater Hudson Valley MLS and a wealth of additional information.