Does anyone utilize a line of credit as an emergency fund?

I went to my local credit union, Wells Fargo, and United Bank and each one turned me down after "checking with legal."  

Quote from @Matt Stull: Hello, I am fairly new to this idea and have wanted to invest in a STR.

Hi Nate - It'd be worth asking the lender for a detailed breakdown of closing costs for this program, as well as an estimate of the interest rate you'd get with today's rates (they'll probably need to pull your credit to do this).

I have been battling with the credit bureaus for 15 years between 2 divorces, and multiple incidents of identity theft (the untold effect of military service).

Perhaps as a syndication or credit fund?  

Hi Shakti, As a lender we do work with US-visa holders as long as they have an established credit score in the US.

Taxes are calculated on the gain (e.g. sale price - purchase price + expenses, broken down fairly clearly by @Jake Baker) not just on the sale price.The tax treatment on sale of a Primary Residence vs.

I think there's a fair amount of play in the budget for what needs to be done.  

You're making a fairly common mistake of designing your castle when you haven't even learned how to build a chicken coop.