Hidden Sub maximising boot space of a car

I am planning on making a Subwoofer in my car that is put on in the space behind the wheel arch that maximises my boot space allowing me to still have a decent sub while being able to fit work equipment in the boot. 
how would this affect the sub?
are there any issues that would arise from this design?
is this a realistic build?
would this be an option for mass production?
would you buy/ make a product similar to this?

Car stereo guys do work like this all the time. Its absolutely not for mass production since the whole idea - which car, what woofer, how much space, etc- is custom to the core. 

I did one exactly like this for the back of my Honda many years ago. Incredible deep bass, which it turns out is not all that hard to do being as its a car, small sealed space, etc. Search around, you will probably find everything you need to know from how to design the sub to how to make and install it in the car, on youtube.
I made an amplified one with a 12" McKenzie driver to fit the space. Sounded great.