James is a landscaping contractor, landscaping the gardens at the Lilly Court Villa in Leeming (WA), which is owned by the Millers. On 23 December 2014 the Millers left for Sucre (Bolivia) for their three week Christmas holiday trip. They left James a key to their compound to continue working on their garden and a contact number for their host hotel in Sucre.
On 10 January 2015, while James is alone at the house and working in the garden, a delivery truck arrives with a load of plants that the Millers had purportedly ordered. The truck driver informs James that the entire load needs to be transplanted into the ground within a fortnight before they wilt. James signs for the plants and then purchases special fertiliser and an irrigation system for the plants on the Miller's account.
When the Miller's arrive at the house on 13 January 2015, they are shocked to find the plants and irrigation system and tell James that the delivery is a mistake because they had not ordered the plants.
They further tell James that, if the plants cannot be returned, he will have to pay for them, as well as for the fertiliser and the irrigation system.
Using the Common law of Agency and the IRAC structure, advise James on his legal position.