Does My Garage require a Mezuzah?

 Yes it does, however as far as a Brachah/Blessing is concerned it depends on the location of the garage. If it is adjoining or part of the house, such that one can exit the car and walk through a door into the house without leaving the garage all agree a Brachah/Blessing is recited. If however the garage is not adjoining or part of the house nor encircled by a gate that encompasses both it and the house  it is a matter of dispute and therefore a Brachah should not be recited.