partnering and multi-family

[Ibrahim Elvis]

hello guys, have a friend who is also interested in investing in real estate and wants to partner with me. he is a good dude and i think we can work together. From your experience, what did you find is the best way of partnering in real estate that works best. should we do like a joint mortgage, LLC, partnership....etc. or are there any other ways of partnering that works best that i dont know about.
secondly, when buying a multi-family commercial building with 6 to 9 units and above for example, should we focus on properties that have more 2 bedroom units as opposed to 1 bedroom? i would think that the units with 2 bedrooms will be easier to fill up as someone can take a friend and split rents or a family with kids. please let me know your thoughts on this. . thanks and merry Christmas !