There are a lot of factors to take into something like this. When you are looking at a SFR you only have one renter to manage as apposed to 4 separate ones. But with multi-family properties if you lose a tenant you still usually have the other 75% occupied whereas a SFR if you lose a tenant, you lost 100% of your income. There are pros and cons to either and it depends on your preferences.
I suggest you do a lot of research before you decide to take the plunge on any real estate venture. You need to determine your criteria (which it seems like you and your friend don't agree on) and go from there. Everyone has their own needs and desires; what's most important is that you learn what works best for you and then become an expert at it.
I suggest you do not go into partnership with this friends if your criteria are not aligned.
Learn, learn and do some more learning! That's the best advice I can possibly give. Once you do that, you will have a better idea of how to determine if you actually have a good deal or not.
Good luck!