Cancellation of Sale and Purchase Agreement- I'm a Buyer

[Account Closed]

As a wholesaler in Washington I am concerned about a Seller who may not fully disclose material defects that affect the value of the home. 

As a wholesaler we sign purchase and sale agreements before the inspection period. If I want to exercise my contingency to cancel the sale and purchase agreement with the Seller. Is there a certain form I would use to fulfill the statue of frauds?

What would the step-by-step process be? 

I certainly would not want to miss a step and get sued for "failure to preform".