I'm not the expert here. I just have had some recent success lately in getting my clients to have their property taxes re-assessed, and lowered that I'm thinking of doing this myself. In todays decling real estate market every dollar helps, and it is better in our pocket.

 Call the assessor's office and ask how it pegs value? Some times it is based off recent sales of similar homes or based on a percentage of your property's estimated value. You'll want to know what that percentage is so you can figure out whether the actual value the assessor is assigning to your home is fair. You will also need a copy of the sales contract to show your purchase price  

1)  your property card at the tax office this will give all current information on your home, make sure it is accurate( this is at the office)( including bedrooms, baths, square feet, and lot size. Oh yea and year built that is a big mistake...

2) Get the appraisers worksheet, this will show how the appraiser graded different components of the home. 

3) Sales records: get comps of homes comparable to yours, dated near the time of your assessment.( call the county to find out when it was assessed)

4) Visuals get photos of your home, and of the comps. Make sure to highlight all your damages or not so good side of the house( DON'T SHOW ALL NEW WORK DONE) SHOW THE FAULTS OF THE HOME... THIS IS VERY IMPORTANT!!!  ANY AND ALL FAULTS. THE MORE THE BETTER EVEN YOUR ROOF, CRACKED FLOORS,CONCRETE UN EVEN ANYTHING THAT IS A FAULT!!!! Plot the comparables on a map.

5) Your presentation: Write out your outline for your case. and make sure it is less than 8 minutes. Put together a spread sheet listing the address of the comps, the sales price, and dates the price per square foot and a description of what makes the homes similar to or different from yours. To make your case you need at least 5 properties but 10 is the ultimate for your case.

 If you can't find comps that sold for at least 10% less than your property's assessed value, just throw in the towel as you will not win the case.  The goal is to prove your case, be kind, and patient DON'T BE OUTSPOKEN OR YOU WILL BE BLOWN OFF.... If your appliances are a decade old and your cabinets are older the score on your card should be lowered.(HINT THE COUNTY'S APPRAISER DOES NOT KNOW HOW OLD CABINET'S ARE, UNLESS THEY ARE FOR SURE ARE BRAND NEW) I hope this helps you out, and I wish you the best....   THIS WILL NEED TO BE DONE ASAP AS YOU USUALLY HAVE BETWEEN 60-90 DAYS OF WHEN THEY WERE ASSESSED.