The biggest airport in the UP, and one of the largest in Michigan, is KSAW International which is located between Gwinn and Marquette on the former K.I. Sawyer AFB. There is an FBO there, but it's pretty small. I talked with the manager a couple of years ago about the flight instruction market in the area, but he kinda chuckled at me and said they don't get too much of that. They don't have any full time CFIs but at the time, they had two pilots that flew for American Eagle that lived there and worked there part-time as CFIs.
They rent aircraft at that FBO and there is a small museum nearby too. I used to live at KI when I was a teenager so the museum was a walk back in time for me, for you it might just be airplanes and AFB paraphernalia.
You might want to consider attending NMU and getting your A&P while you are up there, after becoming a legal citizen of Marquette County and Michigan for lower tuition rates of course. You might even be able to recruit a student or two from the A&P program.
I had a very large house up there, but I sold it last fall. The woods literally started in my backyard, and there were LOTS of fishing holes within 5-10 miles. It was fully furnished, and I kept a small tri-hull motorboat (complete with 8 fishing poles and a tackle box), a pair of ATVs, and a gas grill in the garage. It was a second home that I only used a two to three times/year for fun and to get away. As such, I thought about letting pilots use it as a free crash pad, or a free place to stay if they wanted to come visit the UP.
The UP is very economically depressed and I wasn't sure how much use my house would get as a crash pad or a free place to stay for pilots that were just visiting. In the end, I decided it probably was a nice thought, but I doubted it would get used as I had intended and I didn't want to risk the place being vandalized or my property being stolen, or have to deal with the hassle of cleaning up after anybody that stayed there so I just sold it.
The UP is a BEAUTIFUL BEAUTIFUL place! Unbelievably gorgeous! Mountain biking, downhill and cross-country skiing, fishing, hunting, snowmobiling, and camping are all very popular there. There is also a USA Olympic training center located in Marquette. If you have any other questions about the area, feel free to ask here or in a PM.