If you are going to store gasoline for an extended period (say more than 3 months) consider getting Ethanol Free gasoline and then using a fuel stabilizer in it. (going to cost you an extra couple of dollars per gallon though) Ethanol treated gas is NOT a chemically stable product AND the ethanol also sucks water from the air into the gas, which is precisely why ethanol blended gas it is NOT used for airplanes which often sit for weeks or months on end. (aviation gas is NOT a good option since it has lead in it, a NO NO for modern vehicles)

Since you are in Michigan LOTS of boat marinas sell ethanol free gas (almost all marinas along the Great Lakes do), but there are other places too. Do a Google search ... there is a great website out there " pure-gas.org " that has a state by state listing of stations that sell ethanol free gas, though be sure to call ahead since their updating of their list leaves a LOT to be desired and not every station listed still sells ethanol free gas.