Kalogredis calls that basic fact that a document generally viewed by many as a casual and non_binding document, could atimes still become binding under certain unpredictable circumstances, "one of the traps in a letter of intent," and adds: "My advice [to parties contemplating having an LOI] is to proceed with caution before signing any such document. As a general rule (and there are exceptions), I urge the parties to go right to the final documents and "dot all of the I's and cross all of the T's," rather than go through this interim step of a letter of intent, which has many potential traps."
That is about it for the content, believe it or not; it is direct and straightforward without any fluff or nonsense. You are simply covering each detail so the seller knows exactly what the buyer intends to do. Having an informal letter of intent also allows for easy negotiations.