Bilateral (Mutual) Mistake
Both Parties to a contract are mistaken about a MATERIAL FACT. Either party can void the contract.
Only one party to the contract is mistaken as to some MATERIAL FACT. Generally, the mistaken party can't void the contract (exceptions).
A fact important to the subject matter of the contract.
Mistakes of Value
Generally, the contract can be enforced by either party.
A false statement of fact that deceives and causes harm to another. The remedy is recission.
Overcoming a person's free will by misusing a position of confidence and trust, thereby taking advantage of that person to affect his/her decisions. The contract is usually voidable.
Overcoming a person's free will by threatening the party with an ILLEGAL act. The contract can be rescinded.
One party with superior bargaining power sets the terms of a proposed contract and presents it to the other party on a take-it-or-leave-it basis. These contracts are usually enforceable unless unconscionable.