Depending on your location, you should search on real estate firm websites in your area. A good resource online for appraisal information is: appraisalinstitute.org.
when property values go down
The most accessible source of information on property taxes is the local treasurer's office. It will have not ony a schedule of taxes, but also valuations of different properties.
The Harris County Appraisal District handles property appraisals and taxes. They also provide an electronic system for property owners to file a protest, or accept/decline a HCAD settlement offer.
increases property values and property taxes in poor urban areas
Your appraisal district can advise you on the steps to take to protest your current appraisal, which is what your property tax is based on. A county appraiser may visit your property to reassess the figure. If you don't get the result you want, you might need to engage an attorney who fights to lower property taxes. Find an attorney who will accept a portion of the reduction as his fee.
Usually you will have to go to a government agency to get property tax information. Sometimes you will be able to talk to current or previous owners of the property though.
Depending on the specific laws in the jurisdiction where the property is located, it may be possible for someone to pay off the back taxes and potentially claim the property through a process known as adverse possession. However, the requirements and conditions for adverse possession vary widely by location, and seeking legal advice is crucial in such situations to understand the options available.
The city or county assessor for the jurisdiction where your real estate or personal property is located places a value on property for purposes of taxation. In some states there may be two separate assessors, one who values real property (buildings and land) and another who values personal property (machinery and equipment, cars, etc.). In some states others may act to set city, county, or state equalized values that are ultimately used when taxes are levied. Check with your local assessor and ask if your taxes are based on locally determined assessed values or city, county, or state equalized values.
I don't know if you still have a question about property taxes but here is some information about Illinois property taxes. In Illinois, each County has a Supervisor of Assessments Office. Property taxes are based on the assessed value of a property. In order to determine if the taxes are the same for each County, I would suggest that you research a property in each County valued about the same or call each Assessor's Office and ask what the property tax rate is in each of the Counties. Attached is a website link for all of the Illinois County assessor records. Using the website you can access both online information and contact information. Depending on how you want to research the issue, you'll have the links that you need.
They can be if the city is an independent taxing authority as they are in Virginia. State tax laws vary on property taxing authorities and taxing districts. A recent property tax bill or a call to your local tax assessor or tax collector can clarify what taxing authorities levy property taxes on a specific property. Many communities have property tax information on their websites. Local real estate professionals may also able to provide you with this information.
Property taxes
If you sell the property for more than it was worth on the date of death (or alternate valuation date selected by the executor of the estate), the difference is subject to taxes and most likely a capital gain. Conversely, if you sell it for less and you did not use the property for personal purposes, you can claim a capital loss. For this reason, it is essential that you have records establishing the value of the property on the date of death (or alternate valuation date). Contact the executor or have an appraisal/valuation done yourself if none is available. If you don't get this information soon after the death, you may find it difficult or very expensive to get later and may find yourself paying unnecessary taxes or fees.