In which cases will the buyer (plaintiff) be able to shift the burden of proof upon the defendant?

i am an class 11th student and I'm auditing (non-credit student) student law Studies.


I'm interested in a situation wherein the buyer has paid the consideration to the seller in exchange for the goods, but the seller denies:


1. denies Any contract between them.


2. and also denies Getting any consideration from the buyer.


therefore, Given this situation, the buyer wishes to sue the seller for breach of contract.


I would like to know:


In which cases will the buyer (plaintiff) be able to shift the burden of proof upon the defendant (to the seller) in order to prove the following:


鈥?to prove That he (the seller) didn't get any consideration from the buyer (plaintiff)


鈥? And To to prove there was no binding a contract between them (to prove that they didn't have a contract between the seller and the plaintiff).In which cases will the buyer (plaintiff) be able to shift the burden of proof upon the defendant?
The buyer either has or doesn't have a contract, or at least a cash receipt. If he has neither, he is going to have a hard time selling to the courts any responsibility that he, the buyer, thinks the seller may have. The seller certainly is not going submit those documents, so the burden would fall to the buyer to submit said documentation.