Although it is not directly discussed, it is implied, correctly, that Berlin designed and made most of his own clothes, including his iconic saran wrapped white pants.
During one of the shots of Peter Berlin walking the streets of San Francisco, his voiceover describes himself as sixty years old. At the time of filming in 2003 and 2004, he was 59 and 60 years old, when the film was released gradually in 2005 and 2006, he was 61 and 62 years old.
The on screen credit for Nights in Black Leather (1973) is subtitled "Ignatio Rutkowski, director," but the credited director for that film is Richard Abel (as Ignatio Rutkowski).