Disclose garage converted to living space

[Tony W.]

I have a house that I advertise as a 3/2.  It has 3 bedrooms and 2 baths in the main house, but it also has a garage converted into a 1/1 studio.  I am about to rent it out and my tenants intend to have someone living in the garage conversion.  Do I need to get them to sign a disclosure that the garage is a conversion?  Do I need to be worried about any legal issues from having someone staying in this unit (I am in California).  I have spoken with my insurance guy and the garage conversion is treated the same as the house in terms of insurance so there is no issue on this front. 

If I do need to disclose it, does someone have some boilerplate to do this?