Agree with your assumption.

I also advertise “subject to” deals or “mortgage assumption agreements” for people facing hardships that might be behind on their taxes, divorce or whatever the case may be.

And I'm only using 5% for the appreciation assumption.

My assumption is that I would eventually hit a scalability issue and end up pivoting into commercial, so I'm thinking perhaps I should start with commercial? 

I propose you keep it simple: If the deal won't cash flow at asking price, then at what price will it cash flow, keeping all other assumptions the same.

But most folks feel comfortable at anything more than a year without some other mitigating circumstances.Anytime there's construction involved there is going to be an automatic assumption that your intent is to sell not hold. 

I think it's a fair assumption it will snow more than 4 times per month in the winter.

I have been under the assumption that with poor credit refinancing would be less than likely for me to get approved.

I also like the fact that you're budgeting for management even if your self managing (although I could be wrong on that assumption that you're self managing). 

Assuming the ARV and 3 month turnaround are accurate (big assumptions, mind you), this seems much better suited for a pure flip than BRRRR.Problem is after refinancing you're effectively breaking even with conservative expense forecasting.