What's the difference between 2, 3 & 4 unit buildings?

[James Northrup]

My wife and I will be purchasing a multi-unit building in Brooklyn in the next year, but we can't decide on how many units. We will be living in one of the units and renting out the rest.

I understand the obvious differences: sale price, downpayment, mortgage, repair costs. However, beyond the numbers, I don't really know what to think.

Are these types of buildings radically different from each other?

Which is a better investment?

[James Northrup]

Just to follow up.  We did buy a 2-family house in Cypress Hills, Brooklyn.  It's great.  Saving a ton of money and learning a lot.  

The mayor is putting a couple Billion into this area in the coming years, so we'll see what happens.