Realistically, to give you the assurance you want, you will at some point have to let another professional tax a look.   

You should speak with a real estate savvy CPA, especially if you are factoring in taxes into your decision making.Interesting I may be wrong about the 4% investors tax as it's been a while since I read this.

However, a while back there was legislation to allow homeowners to avoid this phantom income tax.

Perfect house for investor except...The owner has been renting for 5 years and paying owner occupied property tax ($864 for 2016 according to tax card) and I calculate tax as rental will be $3844 for 2016.MV ~$130K but deal is marginal at $110K and fair - good at $100K for investor.How do investors compete against buyers looking to live in the home in SC when there's such a big difference in the tax rates?

I suggest getting a good CPA that understands the tax laws in both countries to make sure you pay as little tax as you (legally) can.Welcome to BP!

this is curious thought process... how does the city get the properties.. is there a city ad valorum tax as well as a county one ? 

I would then lend the money out to fix and flippers at 15 to 20% APR   IE HML  and make the 15% on the 1 mil  that's 150 a year... then make the delta between the 7% bank rate and 15% low side  for 8% spread on 5 million which is 400k a year... there by grossing before tax  a tidy 650K a year...

If we were to sell we would qualify for avoiding capital gains tax as we have only been renting out the property for a year and I was living there prior to getting married.  

You can buy a replacement property with your 1031 exchange and defer all tax as long as the investment portion was worth at least as much as you sell. 

All your profit from the sale of a flip is ordinary business (active) income (reported on Schedule C if you are not using a business entity), and further subject to payroll taxes in addition to your ordinary income tax.