@Tyler Porter Nice to see you are motivated into REI. Seeing as you are starting out I would not recommend a multi-family yet as it can be more complex to manage & maintain. Not saying that its not possible but can be more challenging and expensive.
With fix&flips you are correct that it does have quicker profit but can involve higher unexpected renovation expense, additional holding cost, and higher tax collection so in order to do this is research properties carefully and have a good cpa.
Your last option was find a next home which i see a few option with this. First is find a single family and keep the other as a rental. Second, sell your single family to move in a duplex. And third which is bit coming from Brandon Turner podcast and weekly seminars I watched in the pass is get a FHA loan to buy a new house and get a 203k loan to do improvements while gaining rental income from your previous properties and pay for loan you took out.
So overall these three choices are not easy but they can help giving you some direction and some experience in term of investing so hope this helps.