I recently advised a non-trad about this same topic. Although applying the following technique is substantially less work if you have multiple acceptances and are trying to decide between schools, you could also go through the process before applying.
Most schools have a well-defined policy with hard numbers for increasing COA. For example, a school may add $200 per month per child for children enrolled in full-time childcare. The number will vary among schools, so you would need to call the financial aid dept at the schools you are interested in to decide if what they offer is more or less aligned with real-world market forces. It is also worth considering tuition cost because if the COA goes over the Stafford limit, then you get into grad plus loans, which generally have worse rates and are based on credit worthiness.