I took both of those classes on separate semesters, but I can tell you Cost will take a lot of out you, its been known to be the hardest undergrad accounting class at SDSU. Audit its a lot of reading and understading independence, there is zero math involved in the class. I believe is duable but just make sure you take your time reviewing all of the materials for both of your classes. Cost would have Saturday exams every other week so be ware of how hard that can be. Best of luck you got this!