After working 25+ years, I was approached by my manager to take course work in Statistics. It seems they had determined they needed another statistician and wouldn't I like to be it? After some consideration and talking it over with my family, I agreed. Before I could enroll in grad school, however, the math department decided I needed to retake Calculus since it had been almost 30 years since I took Calculus in college.
I took the first semester at a local community college for about $150. I took the second semester at a local private university for about $4,000. (Fortunately, the company paid my tuition!) Despite the difference in tuition, I found the CC version of Calc I to be at least as thorough as the more expensive semester at the private university. In some ways, it was more rigorous, although your mileage may vary. I would suggest that a CC probably has more experience in teaching calculus to students that are struggling with the concepts than a larger university where the students are expected to have some level of expertise.
I was lucky - I remembered much of my calculus and got As in both classes, then started classes in Applied Statistics. I completed my degree in 2.5 years with a 3.86 GPA while working essentially full-time as well and raising a family. It's fortunate -- the company and I parted ways due to being outsourced, so if nothing else, I have additional fodder for the resume and proof the old dog still knows a few tricks.