Most people have transferable skills (accountants and engineers being good with numbers; people from the service industry are good with customers or high touch business models; marketing professionals know how to build a crowd). 

{I see that the calculators are still {incorrectly} classifying CapEX as an expense}When modelling a project like this, I tend to be very conservative {upside surprises are more enjoyable than downside ones}.  

I just want to model them and hopeful also build a portfolio in the next few years .

They have both proven the model and the street is rewarding them.

Same builder has bought a new subdivision and is building same model and floorplan of our current home at almost 100k higher price points.

Put your operating strategy into an underwriting model.

I have a much different viewpoint, which I think is mainly due to a different business model.

Choose the right firm with the right tools and business model. 

If a deal doesng go through due to a failed phase 1 environmental study and your LP already spent thousands of dollars on the environmental study.

That's the usual model for wholesalers.If you actually close on the property, you're free to re-sell - but otherwise, wholesaling as it's commonly practiced is unlicensed real estate brokering.