joint tenancy and not paying probate

Ohio
My friend and I bought a house under joint tenancy with right to survivorship. we are not married and we both own each one half of the house. If he were to die do I just take a death certificate to the clerk of courts or what to have his name taken off the title, and no probate costs? We dont know what to do and I cant afford to pay an attorney.
We have willsleaving everything to each other. can his family claim anything or take anything, they are not in his will, only I am

... joint tenancy ownership often only delays the probate process. Upon the death of the first joint tenant, title passes automatically to the surviving joint tenant, thereby avoiding the probate process on the first death. Let's look at the example of a married couple who owns all of their assets in joint tenancy. On the death of the first spouse, there is no probate because ownership of the assets passes by operation of law to the surviving spouse. However, on the death of the surviving spouse, there will be a probate unless the surviving spouse creates a new joint tenancy or places his or her assets in a living trust.