Multifamily property dilemma from Charlotte, NC

Hi, everyone, I hope this thread will find you well. I am William, from Charlotte, NC. I owned several single family homes and several town homes. I just found that it was too slow to expand the units. Therefore I want to take a look the small apartment buildings such as duplex, quadruplex , ect. However, I found all of them ( I can found on MLS) are kind of crappy: old (most of them are before 1970) and bad locations. Of course, I am new to multifamily properties so I maybe wrong. My problem is how to find a decent multifamily property ( relatively new, not so bad location), etc?

I am also wondering how you guys expand your portfolio quickly.

Any thought is appreciated.