My step mom is giving me a house and we want to be aware of the best options to transfer ownership in my name, while avoiding any heavy tax consequences.  

Be aware you will have to pay a contractor to give you a accurate bid.

Given that the seller is willing to finance (which I think is good), I'm also aware that without a third-party bank lender I won't have them watching over my shoulder making the normal checks.Is the best course of action to hire a local real estate lawyer with experience in commercial property to make sure I don't miss anything big?

You need to be aware of ALL the risks before you make your decision.

However, just be aware of the seasoning requirement of your down payment for your lender.

Be aware, just because your gc signs this release does not mean subs and suppliers can't lien your property.  

@Joe S.Not that I’m aware of.

Be aware, however, that when refinancing unseasoned property most institutional lenders will limit your LTV to a percentage of COST, not market value, so trying to refi off of the higher market value will be difficult to do.

., a war in Europe, a CEO scandal or even a random tweet by an executive (like Elon Musk). 

Also be aware of prepayment penalties, especially if interest rates do end up going down.