Legal Question in Real Estate Law in California

I don't understand the relevance of someone else's offer to your issues of fraud. In a fraud case you are saying that someone mislead you to get something that is worth less than what you thought you were going to receive.

Yes there is such a law. It is the law that says fraud is when someone tells you something that is untrue, that you reasonably believe to be true, that you then reasonably rely on in doing something you would not have done, or refrain from doing something you would have done, if you knew the truth, and as a result you suffer loss that can be measured in economic damages. Without all those elements you don't have a case for fraud. The situation as you describe it in your vague question contains not even one of those elements.