"Buyer who is serious, ready and able to purchase [crude oil], will sign [an] LOI and all the necessary documents that protect the rights of the Brokers and proceed. There is nothing to lose in signing those documents. This is how it is usually done and this is how it should be."
On Offer acceptance there is either a contract generated or a pro forma invoice generated. Since the offer is binding once accepted, the offer if well enough detailed and advised can and often does take the place of the contract. Customarily in Real Estate transactions the purchase offer itself is generally also the contract for purchase as well. The offer becomes a binding contract once accepted.