Another factor in deciding on an agency type and license type is your desire to adopt. If you are hoping to foster with the possibilities of adopting then you need to select a Private Agency that is licensed as both a child placing agency for foster care and adoption. If you are looking at your Public Agency, have a conversation with the licensing worker to see how they view adoption. Most counties will support their families adopting and will work closely with you. Other counties would like to, but manpower and other factors limit their ability.
Please note: Deciding which agency you want to work with might be the most important decision a new family makes in their journey to becoming a foster family. The relationship you have with your licensing agency is so important. Look for an agency that you are comfortable with, an agency that shows as much interest in you and your children as you do in them.