I need to help my friend, his situation is more complex than normal to some degree. Can you help?

My best friend believes he is suffering from depression, and I believe he is too. But the 'getting help' factor is proving to be difficult in this situation. I have experience with depression with my father being diagnosed with it, after also being diagnosed with an untreatable case of neuralgia, so i am aware and well-educated about symptoms and treatment, although, I do not have enough knowledge to deal with this situation.

Being a teenager, but almost out of school (yes, I am a minor too), the first logical step to seeking help is to talk to parents about getting treatment and getting that help, but the problem is, his parents are part of the issue at hand and from what I know, not the most understanding and caring, or financially stable. He wants help, but he refuses to speak to his family. After witnessing the situation for a little while, and supporting him with all I have to keep him alive, I've decided that he needs additional aid and help as soon as possible, and I'm willing to help him in anyway possible.

As a friend, I want to know whether I, as a minor, have the ability to seek help, book appointments and help him recover myself, without needing his parents permission or a guardian present? And if so, what are the costs and financial arrangements in such a situation, especially for on-going costs like medication?

Any advice on how to deal with this situation would be greatly appreciated and hastely acted upon.