Legal Question in Real Estate Law in California

Civil Code section 1542 says that a general release is not effective as to claims that the releasor does not know of, and even through the exercise of reasonable dilligence could not have discovered, before signing the release. Unless this is a complicated transaction and cancellation, the standard real estate forms will probably be fine. Also, since you are giving a specific release, not a general one, it arguably doesn't apply.

If you're really worried the seller will come back at you for unknown claims after the fact, however, you can both sign a letter agreement or an addendum to the cancellation form that says you are both aware of your rights under that code section, include the entire text of the section, which you can pull off the web, and then both state that you agree to waive your rights under the section. That is the standard format we use when settling litigation that we want to go away for good with no "I didn't know" claims coming up. So it should be more than sufficient for your purposes. As with anything that has not been reviewed by an attorney, however, you must understand that I cannot guarantee any release that I have not seen and approved.

You cannot do without an attorney unless you want to lose money. Contact me directly.