K., why isn't he in foster care and in a....hospital setting? Is he sick?
This doesn't make sense to me, kids this age belong in foster care if they've been removed or lost their parents. He should be in a home setting.
That said. If you are interested in adoption at all then perhaps you can contact the state and find out more. Some parents who adopt kiddo's that are in states custody get a stipend to help support them. If finances are your only issue perhaps that could be something they'd help you with.
Otherwise I wouldn't go. He's starving for affection/attention and needs to bond with someone soon.
If you google the effects of a child that doesn't bond and they can become grown ups with mental issues. They need that bond when they are very very young.