A “letter of intent”  or “memorandum of understanding” can have legal significance.

Occasionally, parties to a real estate transaction sign a written document they prepare called a “letter of intent” or “memorandum of understanding”. It often occurs in the early stages of a transaction and springs from a belief that the document is not legally binding, but merely expresses what the parties plan to do. There are many Connecticut court cases holding that such documents can be treated as legally enforceable contracts. You may end up stuck in a deal that does not contain the terms you expected. 

Therefore, it is not advisable to sign what you consider to be a non-binding letter of intent or memorandum of understanding without having the document first reviewed by your attorney.