@John Davis be sure to check out all the city landlord requirements.Michigan also has an online Landlord-Tenant Handbook that is awesome source of info.Lastly, be sure to join the RPOA investor's group in Grand Rapids.

First of all welcome to the BP Community. 

Your total project cost is only ~ $143k. 3c) Your interest rate is probably going to be in the low to mid 7s, at least4) All states/areas are different, but I usually see with my CFO clients that their property taxes are higher than their insurance, with taxes often 1.5x higher than insurance.5) Lastly, I saw PM fee of 8%, are you paying someone else to manage this?

The agent is the person who will have all the data, when you do comps are they on Zillow or Redfin?

I tried attending one in my local market a couple of times but felt like I was in some hotel ballroom being pitched on how the 12 year-old kid up in front would teach us all how to run to the back of the room to swipe $10K on our AMEX for the secrets of real estate investing.

Plot 1: 2024 market value of $6,900. 45x120Plot 2: 2024 market value of $3,800. 100x94I'm still pretty new to the game, so I have no experience with land deals, ground up construction, zoning, things of that nature, and am wondering what the best play is.Sell one to help with acquisition costs and build an ADU on the other?

Not all beaches are created equal.  

Also, focus on 2 years of job/income stability.Class D Properties:Cashflow vs Appreciation: Typically, all cashflow with little, maybe even negative, relative rent & value appreciationVacancy Est: 20%+ should be used to cover nonpayment, evictions & damages.Tenant Pool: majority will have FICO scores under 560 (almost 30% probability of default), little to no good tradelines, lots of collections & chargeoffs, recent evictions.

Quote from @Don Bessette: I have a 30 plus year tenant that can not keep up with maintaining their unit, it is filthy inside and in desperate need of renovation, all systems are in good repair and I respond very quickly when issues are brought to my attention.It is also well below market rent, and they struggle to pay the current rate.Looking for suggestions on how to gently proceed with the notification to move. 

I always run the numbers as a LTR to be safe. 500k is steep for a duplex but it all depends on what each side will rent for.