Contract Law? URGENT?

Vicky is the owner of farmland. She has lodged an application for subdivision with the local

council.

Tom asked Vicky if she would sell the land to him and Vicky said she could not sell the land

until the approval of the subdivision was given but in the meantime, she was happy to let Tom

“camp” on that part of the land which is next to the river. Vicky and Tom intended that a

formal contract of sale would be prepared by Vicky’s solicitor upon approval of the subdivision

and payment of a 10% deposit by Tom.

Tom asked Vicky if she could confirm the intended sale price of the land. Before Tom started

camping on the land, Vicky’s husband, Simon, gave Tom a letter which set out the sale price

(including the 10% deposit) of the land. Simon signed the document but Vicky did not as she

was collecting the children from school when Tom called over to the farmhouse to collect the

letter.

A week after Tom signed the letter, he proceeded to build a shed on the land and to have

electricity brought to the shed and he also installed a water tank. Vicky knew of Tom’s

building works as the trucks drove past her house on the way to Tom’s “camp” and she had

asked Tom to make sure that the trucks delivering the materials to the site drove carefully

past the house as she was concerned the children could be run over when playing outside the

house

Please advise Tom with reference to the common law of contract. (Based on Australian Law)