I recently signed a contract to have windows installed in my new investment property. The next day I called to cancel the contract and was told that of the $10,000 down I can only get back $4000. I have 72 hours to cancel a contract but as of now they hacve only given me the remaining $4000 and no receipt saying I lost the other $6000 despite my many requests. What all do I need to sue them for the other $6000? Thank You