Inherited Duplex ready to Invest

[John P.]

 Hello everyone, I’m new here and to real estate/home owner. I inherited a duplex from my grandparents. I’ve owned it for 3 years now. I’ve recently moved into one side and it’s nice not worrying about a house payment or rent monthly. I also have had a great tenant. my first family i approved to live in my rental. I know this luck. I’ve dealt with 3 different tenants on the other side in 3 years.all 3 were a nightmare.
So  I’m pretty young and rather lucky to have this situation at hand. Although, I’ve never had credit cards or borrowed money for anything. So I had no credit. This past year I started to change that. My credit is low with no history. I settled for a secured credit card. I have a $200 limit. I only use it to pay for Netflix and Xbox live. which is under 30%.  I pay it on time every month. No late or missed payments. So my credit is slowly but surly building. 
 
 My real objective here is to find out if it’s possible to use my duplex to start a real estate flipping/rental business or just flat out buy more homes without a business. I really don’t enjoy factory work etc so I’ve always done my own work. I am a roofer, painter, dry waller, jack of all trades self employed individual. I want to stop the hard work and start flipping and buying long term rentals (Of course I’ll do all repairs and updating myself) I just have no clue where to start or who to talk to. Any solid and good mannered adviced would be extremely appreciated.

(I live in a small rural Midwest town) duplex is paid off only pay taxes and utilities, upkeep etc. last I knew it was worth around 150-175k that was before a new school, sewage and fiber optics. I imagine value has risen. My taxes sure did. 

Thank you,
 John