An option for you is a post-baccalaureate program in art. These are 1-2 year programs for people who already have a bachelors in another field. While the cost per year may not be cheap, it may be cheaper than the 3-4 years it would take to complete a second bachelors. Some examples:
SMFA Boston: https://smfa.tufts.edu/academics/post-baccalaureate
Brandeis: https://www.brandeis.edu/fine-arts/postbac/index.html
MICA: https://www.mica.edu/applying-to-mica/graduate-admissions-process/apply/post-baccalaureate-program-admission-procedures/
You don’t state where you live now, so I can’t suggest any inexpensive programs that are good and that are near you. If you don’t mind giving out your state or a region, I may be able to help more.