DHL will send you a email/text to pay any taxes or duties and then it will be eventually be handed off to Intelcom or another shipping company once it clears customs. I live in Winnipeg so it's always Intelcom.
I also live in a house so it makes things easier to deliver. I don't know what it's like to deliver to an apartment.
If you don't pay DHL the customs fees then it will probably be handed off to Canada Post for final delivery and the collection of custom fees.