Licenses are required for all residential building contractors Minnesota who contract with a owner of "residential real estate" to construct or improve dwellings by provinding work in more than one special skill
Permits on electrical works on their own property can be requested by homeowners through the page https://ims.dli.mn.gov/ims
Contractors who have a state license don't need to obtain a local license for work that is covered under the state licensing laws.
Homeowners should always verify if a Minnesota Plumbing contractor hasd an active license by visiting https://secure.doli.state.mn.us/lookup/licensing.aspx