Partner up with an experienced contractor. This will make a huge difference on your time, budget, and sanity. Get at least three bids and check their licensing credentials and status with the MN Department of Labor & Industry: http://www.doli.state.mn.us/ccld.html .
You may want to consider talking to the people at Castle Remodeling â€“ they have a great reputation in the community - here is their site for more information: http://www.castlebri.com
Your contractor should be responsible for pulling all the permits with the City and ensure compliance of codes. Good luck and I hope you enjoy the process.
Wow, you are moving from Hawaii to Minnesota! That will be a change...hope you wait till it warms up here so it isn't so much of a shock.
As for converting a duplex into a single family home, please read this information bulletin from the City of Minneapolis regarding the conversion, and a link with additional info on the process:
If you have any other questions, please don't hesitate to ask!
I really don't think that the city or county will care. In MN zoning ordinances normally read that a property may contain a less dense use but not a more dense use. In other words a property that is zoned to 2-Family residential can normally have a single family residence - but not the other way around. That said you will need to check with the city in which the property is located first.
Architecturally you may have some more headaches. Many duplexes are set up such that a party wall is between them and in some cases this wall is made out of concrete block. There are too many variables at play to be able to give you a complete answer here. My recommendation would be to talk to a contractor once you have a property selected and hire a residential designer to come up with some ideas for you. I would be happy to recommend both for you if you like.
I have seen this done IT LOOKED GREAT !