7 unit near college

[Yiyi Guo]

Hi everyone! My name is Yiyi, I'm a newbie looking to house hack in my area, I saw this one in area I like:

http://www.zillow.com/homedetails/2642-N-Frederick...

It looks like a good deal to me, looks like it would fit in the 1% rule at a glance, tenants is probably easier to handle because it is in the college neighborhood and it has a bunch of studios in it. 

However the house is very old but it looks totally livable from the pictures, but it could require some repair upfront and down the road. Another concern is that it is a 7 units, more than 4 so it's not residential anymore? What is the difference? Just tax? Anything else? Is this something I could possibly get an FHA loan to finance it?

Thank you!