My garage desperately needs more depth in order for me to park my cars in it. I checked and it appears that my city has a 20 ft setback from the street, and my garage is 24 feet away. I could potentially gain 4 feet, which would be enough. My house is on the left in the photo.

I am having a hard time visualizing what can be done, however. I would like to only extend the garage and not touch upstairs. What would that look like? Would I have to sacrifice the upstairs deck?

How can I make it look good with my neighbor's house on the right? Houses are not attached (there is a small gap that runs between the homes).

What are the structural implications? Do I need an architect/structural engineer, or can it be done without?

Is there anything else I need to think about? I figured I'd need to redo my driveway at the same time, anything else?

And finally, what could this type of project cost?

Thank you, Houzzers!