Multi family home for cheap. Help!

[Jacob Charter]

Hey I live in canada and I found a guy selling a multie unit building and I just have some questions. How many units until it becomes commercial?What are the down/ upsides to either residential or commercial? I want to buy this place with cash fix it up, get it appraised and get a refinance to pay my lenders back. Does my credit affect the refinance in anyway or does it strictly have to do with how much I appraise for?