If I understand your question correctly, you received real property under a will, but your grandmother's name is on the deed, not you, preventing you from setting up a payment plan in the taxes. You didn't say whose will it is, but if it was your grandmother, then the will has to go through the courts (this is called probate) before you can be put on the deed. The administrator of the will -- the court-appointed person responsible for disposing of the dead person's property -- has to be involved in dealing with the tax authorities to protect your rights until you can legally be put on the deed. It's puzzling why you have another property in your name, and I can't tell if the two problems are related. I suggest contacting a real estate attorney immediately because you mention that an attorney or agent may not have filed papers properly. You may have a very short period of time to deal with the property still in your grandmother's name or else your rights may expire forever. Also, if there is another house in your name, you should talk to a lawyer to come up with the best way to use it (selling it, living it, and renting it seem like the three main options for your situation). An ideal choice here for you is a real estate litigation attorney in case you need to fight the tax authorities or the attorney and agent who didn't file papers correctly. Again, I recommend getting an attorney immediately.
I agree with the first answer. You must first establish yourself as the Executor or Executrix of your Grandmother's estate, if nobody else has ever done so. That way, you will be granted the Power to sell the house and have a basis for doing whatever else is needed in her estate. If the estate was never filed properly, then hire an estate attorney to look into it for you and follow up with it in Bklyn Surrogate's Court. You may also ask the same lawyer about the other house if your name is on that deed.
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