The numbers are slightly off but the deal should still work, the main problem is she’s only willing to give me 2day(48hr) feasibility period when I usually request 10-15 day due diligence.

Asked my NACA representative if it would be feasible to hit a mid-August close date, and he said yes. 

That being the case, how feasible is to have a BRRRR strategy on turnkey properties given the desire the pay back the HELOC, then repeat?

They can tell you if it's feasible or not.

Is that something that is feasible?

In all actuality, this can be done in your first year in real estate but not very feasible... 

So to use the house as a tool to buy an Income Property is not feasible right now, until it is sold.

Also, I know that if I connected the two structures with a deck or carport, it could be considered an addition in some ways, would this be at all feasible using a mobile home as an "addition" to a traditionally built duplex by connecting them with a deck. 

You have a feasible plan.

I can't tell you what terms you can expect based on the lack of info, but with regards to the actual term of the loan you could feasibly expect a 5-year fixed loan with a 20 - 25-year amortization.