How much is tuneup costs for this engine? on 2005 Cadillac DeVille

Have not tuned engine close to 100K!
Funds are limited.
Thanks for any info.

Asked by for the 2005 Cadillac DeVille
dealership =$400, independent shop =$300, student or a wannabe =$150, yourself =$40, satisfaction of doing it yourself...priceless
2 answers
approx 300.00 labor and plugs depending on labor rate in your area. if it needs more that would be extra