Q: What rights does a tax payer have if they disagree with their assessment?
The FIRSTthing that you should do is to contact your assessor. Most times an issue can be worked out before having to go to the BAR or further hearings. It's important to note that you can see your assessor ANYtime during the year. In fact the earlier the better. There's no need to wait until Tentative Roll Time (May 1st). It's more advantageous of you to go there during the summer or fall when your assessor isn't bogged down in a mountain of paperwork.
If you meet with your assessor and you come to an agreed upon conclusion, then you're done. It would be wise to get documented evidence of said conclusion in case something gets lost, your assessor leaves, etc. If you do not get an answer that you feel comfortable with, then you have the right to take it further. Your next step is to go to the Board of Assessment Review (BAR). They meet at least once per year, around the 4th Tuesday in May (also called Grievance Day), to hear the property owner's side of things. They also hear the assessors at that time. After which they come to a conclusion (without either party present) and notify both parties of it.
If you feel that you still haven't come to a successful conclusion, then you can do one of two things:
1. Go to the Small Claims Assessment Review (SCAR). SCAR is only available to owner-occupants of one, two or three family dwellings that are used exclusively for residential purposes, or the owners of vacant land that is not of sufficient size to contain a one, two or three family dwelling. Information regarding SCAR is available online from the New York State Unified Court System.
2. Seek judicial review by commencing a tax certiorari proceeding in New York State Supreme Court pursuant to Article 7 of the Real Property Tax Law. At this point an Attorney should be obtained.
If, after all of that, you are still not satisfied, then you can go to an Article 78.