According to our general terms, in the most cases (98%) the owner or his representative will be waiting for you at the apartment to welcome you, show you the apartment, give you the keys and inform you personally about all the details of it, instruct you how to use the equipment in the apartment, rubbish removal, grocery store location, nearest metro stations etc.
But there can be some cases when you have to go to the office and pick up the keys. You should read thoroughly the specific terms and conditions for your desired apartment in order to find out how is the procedure in your particular case.
You need to pay the remaining balance as well as the refundable deposit once you have arrived to the apartment, checked that everything is working fine and the keys are handed over. You have to deliver the keys back at your departure.