Greenwood Cemetery

My mother passed and was buried in another cemetery. Her sister inherited the 2 plots my mother had purchased in the 60's and gave them to me in the presence of a Greenwood "official." A few years later, I went back to find the plots in order to sell them, but the old man in the office could not even FIND the plots! What kind of cemetery cannot find plots at all???!!!! To this day, I do not know where these plots are located! That-is NOT service!