Legal Question in Real Estate Law in California

You are creating a rather complicated legal situation here, as well as raising tax issues both in the transaction and once either of you passes away. The two main issues are a) if you make him a co-owner when he put no money down, you are making a gift of 1/2 the equity in the property, which may create a gift tax issue; and b) he will be paying the mortgage out of community property income, giving the wife a claim to the property in the event of divorce or his death. You may be way better off taking title in a family trust rather than as individuals. You really should talk to a local estate planning attorney who is knowledgeable about inter-generational transfers and community property issues about how best to do this.