I urge everyone to contest the valuation on their property by their county. It is very beneficial to have your property taxes lowered, and you can do this by going to your County Tax Appraisal website. See that we’ve included your county link below. You can do all of this online. 
What you do is claim that your home does not fully compare to the properties in the area. It’ll ask you to submit details. *This is where I would take pictures of everything wrong or outdated in your home. Put everything down and send in the pictures. It will ask you what you think the value of your home is and here it’s helpful to claim it as whatever your taxes are currently.
Ultimately, the good news is your home is going up in value. The bad news is the county wants more money.
Most of the time, if you contest their claim then the county will reduce what they are asking by a little. Your taxes will go up. But usually not the full amount they claiming. IF you protest it! 


http://dallascad.org/
https://www.tad.org/
https://dentoncad.com/
https://www.collincad.org/