Estate - IRA - Trust

My mother and father recently passed away. There was an IRA that was my mom's, and my dad was the benificiary. When she passed it went to my dad. When he passed it went to his estate. Is there anyway to avoid estate or personal income taxes on this amount? We had thrown around putting the money into the estate. We are putting the family home in the estate. If we put it in the estate do we pay taxes on it if we were to for example need to fix a fence at the house that is in the estate?