Exchanging 1 multi-family for 2?

[Bob McKee]

Hey all. Just joined and posting for the first time. I have historically made gains living in places then selling them. For the first time I am looking to sell a multi-family I never lived in and buy a new multi-family. My concern is that area I am selling and buying in are very different from a pricing perspective. So do any of you know if I can sell one 2-unit place to buy two or more multi-families? Or does it have to be 1 structure for 1 structure? If the latter, can the new place have both apartments and a commercial unit (like a bar)? Thanks all! Bob