Stick to Your TypeWarren Buffett once said, “The difference between successful people and really successful people is that really successful people say no to almost everything.”Apply this principle here:Decide on your property type.Say no to anything outside of that type.You can always pivot down the road, but starting with focus is crucial to building momentum.

It's likely they may even use data of SFH with similar lot and building square footage.

Building small units in small counts is expensive development.  

We are building off a pre-existing building structure. 

I would like to build several (2 - 6) "shipping container" type homes for either short, mid or long term rental.

You can use this property to hedge any others that you add that may only cover themselves, or require supplement until they are paid off.HOWEVER, if you have decided that your goal is to use Real Estate as a stepping stone to build wealth by upgrading the property you hold each time (condo to house, house to 4-plex, 4-plex to 8 unit, etc) then I think you are right to sell now while you think the property is at the top of it's appreciation.It will be hard for anyone on BP to tell you what to do as we don't know your goal.You are right. 

The goal is to slowly build a real estate portfolio and get to a point that I can eventually sale my business. 

But that extra $7200/year will go a long way in paying down your loan faster, build up another downpayment fund, pay off other debt, etc. 

I looked into a program that is called the rei accelerator and they said they will guarantee me a deal of a 60+ unit apartment building in the next 4 months and i will get to a closing table and generate $20,000 a month off my first deal with working with them.

Quote from @Breland Clark: I would like to know more about developing land and subdivisions for new builds and apartment buildings. talk to the land development arms in your city or state.