You can sue the builder for "breach of contract," or violating the terms of your agreement. If you believe that the builder lied in the first place about what he would, could, or was able to do, you could sue for fraud also. In this lawsuit, you could seek to terminate the contract (get out of it), get your money back, and possibly get other compensation (e.g. living expenses, if you had to rent someplace to live because the home is not done); or not terminate the contract, but get compensation for costs (like living expenses) you have incurred, and/or seek "specific performance," or a court order requiring the builder to complete the work within some specified period of time. You should consult with an attorney to better understand these options, the amount of compensation to which you may be entitled, and the cost and time involved in a lawsuit. A lawsuit is the only way to get compensation and/or force the builder to honor its obligatons.