Great conversion. I'm in the same boat, the RV thing just isn't big enough. I've seen several grain bin conversions looking for ideas. I'm leaning towards a pre-built shed that can be delivered by a truck and then finish the inside. Also kicked around converting a shipping container into a cabin. If I had time I'd just stick build a cabin but still working the 40 hour week, busy with kids, and property 2 hours away I could only work on it a day or two a week so having something dried in from the start would be required. Big issue with any metal bulding is condensation, do you have any issues with that?