Alternate uses for a basement?

[Blake Williams]

Hey everyone, I'm a new investor and I just purchased my first rental property recently!  

I bought a duplex, and I am currently living in one unit while renting out the other.  I don't currently make enough to cover the mortgage and expenses with just the rent but I will when I move out.  

My question is this.  I have a basement with a good amount of space that's not being used.  I was told I could fix it up into a studio apartment because the only way to get in the basement is from outside anyway, if doesn't attach to the other units. 

Someone else told me I could turn it into a storage unit and rent it out that way too.  

What other options are there for renting out an unused basement, and how much money and work would it take to repurpose the basement for that use?