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.

So I'm under renovations for my first property and I used a conventional purchase and renovation loan, not knowing how tedious the draw process would be for me and my GC, but saw it as the most convenient way to fund the renovations.Doing our best to communicate with each other to ensure a smooth draw (fill out work completed form, get inspector out, review from both HUD Consultant and lender, send for signatures, 3-5 days of processing).

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.

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

As an RE Agent and an investor primarily in Los Angeles and Orange County,  I just recently went through this process myself! 

Each area has pros and cons based on why you're investing and the life resources you are able to allocate.

NOI is what it is, and is property-based for easy comparison.