Thank you everyone for the thoughtful responses!
I've decided not to accept the offer of the free mobile home, but keep the Airbnb concept. It is too costly to renovate and move the structure in comparison to a new build on site.
My plan is now to buy land in northern MI, where I've done market research on short-term rentals, and build an A-frame vacation home. This is going to be the most efficient use of my money and will require a small startup for a healthy revenue generating business. The architecture of the A-frame and interior design will set this Airbnb apart from my competitors. In addition, the property is going to have many amenities, such as being waterfront, having a hot tub, and having an indoor and outdoor fire pit.
I have found a few Airbnb hosts in northern Michigan that have multiple properties. I have checked their listings to see what they charge and how often they are booked/how far out they are booked, and more. I am very excited about bringing this idea to fruition.
Thanks for all of your input!