Looking to buy my first investment property

[Lolo Druff]

I am looking to buy my first investment property, and my goal is to continue building this portfolio every year until I can live off my rental income entirely. I have about $400K to deploy, but would prefer to buy several duplexes rather than 1 more expensive building. I live in CA but am open to investing anywhere that makes financial sense. Cash flow is important of course, but so is appreciation, so I want to ensure I have a balance of both. Is it wise to buy some units with high cash flow and low appreciation, and others with lower cash flow but high appreciation to diversify my portfolio?  

I was looking in Columbus OH but the market is so saturated and it's been difficult for me to find cash-flowing deals there. Any deal that I've found seems to have sold within the last 2 years, and its alarming as to why it's back on market again unless they have problems with the building and/or tenants. I'm open to all suggestions regarding different cities that meet my requirements and would love to chat with some realtors who have local experience working with investors.