0.16 acres and I would say $180,000 or less based on the comps. 

Are most lenders looking at my W-2 history and DTI to determine whether I qualify for the refinance or is it more based on the asset and/or its cash flow?

You'll bring a downpayment based on the total project cost and you can get seller financing to help with some of the equity injection. 

So there are a few ways to look at this, the 1st question is are you sure your renovation’s will double the property value, most renovations on primary residences, your lucky to get 60-70% of the dollar cost back out upon sale, so really nail down your comps, than you have basically a math problem if your rate on your primary goes up how long if ever before that extra payment is more than 400k in taxes, that’s just a simple calculation to help you decide, but I suspect you actually have a different question here, from a purely financial perspective my guess is the best option is to do anything to avoid that tax hit, but one of the reasons to make money is to spend it on things that you enjoy, based on your overall financial picture and a subjective view of how much enjoyment you will get out of a renovated home, you should decide if you want to roll your profit into another deal or “cash-out” your winnings, I love cars and I’m willing to spend more than is fiscally smart on them because they bring me joy, there is nothing wrong with that, but i don’t think it’s a fiscally smart choice, without knowing your exact property id imagine a renovation would fall into that category, so that’s the terms I would use to decide.

I believe he’s based in the Seattle area.

Deborah Saddler, the information that I'm organizing at this time is more based around RE definitions and concepts, as opposed to formulas in Excel.

But now that the house is done you get a renter in there and get a lease in place and now you can get a 75% cash out refi based on new value. 

-Taking 10% reserve for vacancy, PM, and Capex-5% for repairs -All other numbers are standard values based on my area.

What you need is data on what rates/costs/terms you can get on DSCR and then base your decision on real figures.  

When it's tenant occupied and time to refinance, would the commercial loan be based on the 700k total?