Making deductions without informing me!

On the weekend the sales guy at silverlakes told me on the phone that I have to pay a fully refundable deposit and that they close at 15h in the afternoon to 'keep' a car. I told him after the test drive I will do my financing and then sign all I need to sign. He said all will be fine. I got there just before 14h and after a huge struggle he eventually told me that there can not be finance arranged as the finance lady has already left(apparently finance close at 13h) which he never told me. On Sunday requested that my deposit be put on another car, but I couldn't get to them. I then asked for my deposit back. Now they tell me that my "fully refundable" deposit is going to be less 1%. and that usually when a client test-drives a car they do not refund....so they are doing me a 'favor'. Nothing of any deductions was communicated to me at all. This is day-light *******....if they informed me about the deductions I probably would not have paid the deposit!