A good question.
A local answer.

List drive time separately from sightseeing time before fixing accommodation, especially on the return to Perth.

Confirm who installs the seat and whether the company can replace an unsuitable or damaged one at pickup.

Map the actual walk to Elizabeth Quay and the station, particularly if you will carry luggage.

The ferry is a short scenic link but may not run when you want to return; plan an alternative way back before the evening.

Check airport taxi and rideshare operations and public holiday notices for the exact year of travel.

Check driving time, child rules and whether a farm offers picking on your chosen day rather than assuming every orchard does.

Check the current sightseeing operator's route and stop list; a stadium stop can change with events.

Check parking cost and height at the exact accommodation, not just whether the listing says parking is available.

Map the last leg from the stop to your hotel before dinner, especially on a quieter weekend street.

Build a second short stretch stop into the plan because a toddler's needs rarely match a single fixed break.

Alternate long tours with shorter city or Fremantle days so early starts do not dominate the holiday.

Check the rental branch's staffed hours and late-arrival policy against your flight number before reserving.