Agree with other posters. If you chose to decorate the apt, without getting prior approval from the landlord on your decorating choices, or an agreement on who pays for what, this is all on you. A landlord expects to get his property back in the same condition as he gave it to you. He may be thrilled that he got his property decorated without having to do it himself & so thrilled with what you did that he'll offer to pay for some or all of it. But he also may be very, very ticked off at you doing this without his knowledge or consent. You may even lose your deposit if he chooses to claim that he needs to retain the money to undo whatever decorating that you did, to return it to its former state, such as painting brightly coloured walls back to basic white.