According to Reddit: https://old.reddit.com/r/PersonalFinanceCanada/comments/10eesaj/those_of_you_who_own_property_what_advice_would/

• Buy water alarms for the basement near the main water line, washer, and dishwasher
• Deep clean the vents and dryer vents
• Buy a back up sump pump
  • Run it sometimes
• Get life insurance that is the amount of the mortgage
• Have at least $15k saved up in addition to the down payment
  • Calculate closing costs
• Introduce yourself to the neighbours
• Change the furnace filter
• Do a full inspection
  • Test nooks and crannies for drafts
• Get a second opinion on the mortgage