Question Description

I need help with a Business Law question. All explanations and answers will be used to help me learn.

I need help answering the following three questions:

1.  Steve buys a house from Jim. There is no written contract.
However, Steve pays the purchase price, moves onto the property, and begins to
build a new garage. Jim seeks to evict Steve from the property stating that
there was never a valid contract. Is Jim likely to succeed? Why or why not?

2. Tony contracts with Paulie for Paulie to build him a house.
They contract for a particular brand of pipes to be used. However, Paulie
decides to use a slightly cheaper brand that is of a slightly lesser quality.
Tony claims that this breach of the contract allows him to avoid the contract.
Is he correct?

3. Frida agrees to sell a car to Johnny for $900. However,
Johnny reneges on the written contract. Frida is able to find another buyer for
the car at $700. What damages may she recover from Johnny?