I have done transactions involving billions of dollars, none of which needed an agreement to be notarized. In one trasnaction I did, it had over 30 agreements, ranging from IP license to stock purchase to registration rights. All you need is the signature page, and in 99% of the cases, a copy of the signature (not even the original) is enough.
I don't know where do you practice or if you are a U.S. lawyer.