Standard Contractor Agreement? Nah.
There is no "standard form" that will protect you.
You need specifics about your project: payments, material grade, line items including sq ft, dates, trades that require a license listed w/ proof of license. etc. You also need to make sure they are properly insured for both General Liability as well as workers comp (workers comp is rare for contractors to have, but you should at min make them sign a waiver of liability for you and the property.) Insure they are going to get permits when required and indicate who is paying for those permits. Also you should indicate what happens if you want to fire them, or they want to fire you. As well as what venue will moderate if there is a disagreement. i.e. if you agree to mediation then they can't sue until they go that route first.
This is the #1 failure for new and seasoned investors. Making sure everything is properly documented and incredibly detailed is vital to insure what you believe you are getting is what the contractor is promising. i.e. "install wood flooring throughout" could mean they install wood flooring, but don't finish it, or used engineered wood when you thought you were getting solid. That difference can/will add up to thousands of dollars.
I would suggest getting a pro to help you do this AT LEAST the first time around....but I am a pro that does that, so I am certainly biased.
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