Owner, in email exchanges I have retained, repeatedly stated that the cost of the rental was $400 with a $200 pet deposit/fee. He used deposit and fee interchangeably. He always distinguished between the rental cost and the pet deposit. He used the word fee in the rental contract. After the rental period, he refused to return the $200 (I left the apartment in pristine condition), and for the first time stated that the $200 was a non refundable rental fee for the dog.