Even though I am contributing financially to the purchase what paper agreement can we make that give me ownership
Your name should be on the deed. Hire a family law attorney to draft a domestic partnership agreement to protect yourself
You should consult an attorney as to a domestic partnership agreement and/or a deed to add your name to the property after closing. Your name not on the title means you have no ownership interest in the property and you are in a very risky position as far as your financial contribution both before and after closing on the property. If anything happened to your boyfriend, like his dying, you would have no interest in the property and his family can force you out, if you and your boyfriend break up you would be looking at a very expensive and long legal proceeding to claim or recoup any interest in the property.
You would need to be on the deed or you could lend him the money for a 2nd mortgage on the property.
