You basically have a 450k mortgage now.

You need basically a ton of savings to cover you?

Construction should be about 5-6 months for a standard basic buildout.

The plan would be to basically use my HELOC as my new checking account, sending all of my direct deposits and income to this account (as explained in all of the 'pay off your mortgage in 5 years' videos).

I was then quoted for about $60/mo but the problem is they only want to do their basic coverage which doesn't cover water damage.Any suggestion on what should I be getting as a coverage and why?

This money is going to go towards my down payment for my first property, I just have to wait for it.I am in contact with a real estate agent and a PM and am basically ready to go.

I'd suggest sending a follow up email (copy/paste to all 8) reminding them, and also send the application link and your basic criteria. 

You may want to work with a "Design-Build" firm which is basically a combination of architect/engineer and builder combined.

You basically assign your rights to somebody else (investor) and they perform on the contract you negotiated.

Lastly, read a book on the Pareto principle and apply it haha.