Legal Question in Real Estate Law in California

You can sue him for specific performance which means the court will order him to sell it to you if you win. As you are doing that file a lis pendens on the property which should make it very difficult for he to sell the property to someone else. Or you could try dealing directly with the bank because after all they are going to foreclose on him and may own the house soon.

I agree with the foregoing, but before launching immediately into a suit, try to verify that all conditions precedent to the owner/seller's duty to perform have been satisfied, otherwise the suit would be premature. Note that there is a doctrine of "equitable conversion" in California and most other states which holds that once a buyer has met all preconditions applicable to his right to close, equitable title passes to the buyer and the seller thereafter has only a bare "legal title" which he is bound to convey upon the buyer tendering the balance of the purchase price.

You need to review your contract and make sure you have done all that is required of you, and that you have tendered, or a ready to tender, the balance due. Also, look for any terms that might require you to mediate or arbitrate rather than, or before, bringing a lawsuit.

I agree that a lis pendens (Notice of Pendency of Action) should be recorded and filed immediately after the lawsuit is filed. As a practical matter, you'll need an attorney to do this.