I don't know if this has been brought up before, I went to get a 60 day extension based on family, at immigration today in Jomtien, ChonBuri.

As usual you need to fill out the TM7 form, one photo, your passport, wife's ID card, and tabien ban. Although I am not on the house book, my wife and son are, and the property is owned by the mother in law.

But anyway.

You now need to show contract of residence, for extensions as this is now the new policy!

Even though we don't actually live at the address on the house book, a signature from the mother in law the owner was suffice on a copy.

But I would have been in a pickle as I have never had a contract for my rented accommodation.

Just a warning if you don't already know.

Yes the general policy of that office to require some form of contract for one year extensions has been reports but all further reporting and exceptions are good to see.

For 60 day you should not need more than wife (or mother-in-law) signing a paper that you are staying with her - this extension is designed for short visits and there should not be an need for a "contract". As you apparently obtained the extension believe you have proved that. For one year extensions they have been strict on some form of accommodation contract for some time now (at least if not obviously living with spouse).