You're starting out an investing endeavor with the willful intent to mislead, lie, and/or commit mortgage fraud and insurance fraud, and you've posted it on a public forum.

There was a huge storm yesterday and the entire basement and main floor are flooded because the house doesn't have a sub pump.

All of this is in emails and the intent seems to be there that a new lease is supposed to be signed for my new roommate and I.

To cover yourself, its probably always best to send a letter to the current occupant letting them know of your intentions. 

Not exactly sure what line of work you're in now but as a caveat if you have no other source of income, do not leave your main stream. 

My main objective for signing up is to learn about real estate investing and specifically multi family.

This is how many turnkey properties are sold (aside from hucksters in NJ), and is the main reason why those properties don't appraise for selling price.  

My main concern would be the vacancy between tenants, and cost associated with a tenant moving out like paint and cleaning.   

I would be very careful commercial in small towns can stay vacant for EVER and a Day.just drive through any small town between Dallas and New mexico.. look down the main street.. nice brick buildings 90% vacant then on the outskirts of town a walmart and the associated fast food joints..the resi might work.. and maybe you change the commerical to cheap storage but put NO value in its cash flow would be my advice unless there is some compelling reason you think those would be leased.. if there was demand they would not be vacant would be my thought

And my main driver an investment is what CoC return is.Now with that said, I have started to look at more investments with a lower CoC (as I have more financial capacity now) and a higher IRR.