There is no longer common law marriage in nearly all the US States. Marrying him will not result in bond. Obtains a visa for him can cost over a thousand, perhaps two thousand in USCIS Government filing fees, alone.
If you cannot afford an attorney, then it is unclear that you sponsor him for a visa, which creates additional complications.
You may need to make some tough choices, such as emigrating to his home country. Good luck.
This is general information, not legal advice, and does not create an attorney client relationship.
That is a VERY HIGH bond.
That makes me think that your BF has more than just being in the US 'illegal' as a problem ... Criminal Conviction perhaps???????
We can't help you find bond money.
Keep in touch with his lawyer.
PROFESSOR OF IMMIGRATION LAW for over 10 years -- This blog posting is offered for informational purposes only. It does not constitute an attorney-client relationship. Also, keep in mind that this is an INTERNET BLOG. You should not rely on anything you read here to make decisions which impact on your life. Meet with an attorney, via Skype, or in person, to obtain competent personal and professional guidance.