I believe we might match up eventually, but I don't have anything on recent Renzes.
We have Dorothy Renz, who was born in Columbus in 1888. Her father was William Renz, who I believe was the William shown as living on Summit St. in the 1880 census and the city directories of the time.
Does this make any connections for you?
I know I found that many, many of the Renz family are buried in Greenlawn Cemetery in Columbus, including our Dorothy and her family. Their records are on microfilm and I have used them in Salt Lake City. You should be able to get ahold of them. They are very informative, giving parents, etc.