First of all, you will need to know where your property line starts and end. Therefore, you should contact surveyor to determine exactly how far you can build the garage. You subdivision might already have the survey online and I can help you find this survey if you contact me with your address. Second, before you start building the garage you will want to get a permit. If you build it without a permit, then when you want to resale your property it might or might not add additional value to your home. Please feel free to contact me if you want me to help you find your subdivisions survey map online.
Sean Heideman, Realtor