This is an early Spenser mystery book published in 1976. There were references to a "leisure suit" and another to David Frye. I doubt if anyone born after 1980 could identify the references. (David Frye was an impressionist in the 70's. He was particularly good at imitating former President Nixon.)
I was looking for an easy book to read and I knocked this off in a few hours.
This book was somewhat interesting as it described Spenser's and Hawk's early uneasy friendship and business relationship. Susan is only a high school guidance counselor, not the psychologist she is in the more current books.
If you're looking for easy reading, some mystery and very good dialogue, check out the Spenser mystery series.