Familial verbal agreement with notarized document outlining terms.

Or can my parents just notarize the paperwork and get the building permit?

We have always required that parents sign and notarize a guarantor form for each student.

From my research, trusts have a one-time fee (after you acquire the trust template) and that's the recording fees at the county and notarizing. 

If not are they any other options ?

Very rare on the west coast that the recorder will record said contract. it has to be notarized plus if an attorney gets ahold of it and you slander their title your in for a world of hurt.. may in your market but in most thats a bad play. 

If there is an agreement to be signed does it need to be notarized?

I am able to send him paperwork and have him sign everything and he can notarize everything in Mexico.

Texas allows online notarizing which will help speed things up for you.

My plan was to sign and get the docs notarized at the US Embassy here but the issue is I'm in a time zone 12 hours ahead so it won't be possible to do that the same day I receive them.