Various pre adoption (via DFPS)

Hi all, My husband and I have some questions about adopting via DFPS. Hoping some of you may have an answer or experience to share before we apply. (We attended the mandatory meeting early 2017, and attended a few training courses from a private agency but will not be using the agency in future) We have 4 children and would love to adopt a sibling group of 3. State requirements state no more than 6 children in the home. Do they class adult children? My oldest is 21 and attending college but living at home. We will be moving out of the country late 2019. I haven't found requirements for residency post adoption. Can any of you advise? Our adopted children will gain dual citizenship. Does the state look down on parents adopting prior to moving overseas? Sibling groups qualify for adoption assistance. However, is there an income cap for this? We currently earn around $150k but that figure will drop once we move and the cost of living will sky rocket. I would feel crummy accepting the funds in America, but they will be highly appreciated in our future home. When we move university is subsidized by the government therefore its free. We'll also have universal healthcare, so we won't need assistance with those items. Thanks