However, you really need to consult with an attorney who can provide specialized advice to you. 

Since you want to sell your coworkers houses you’ll def need a license for that.I’d also set up an llc and get a business bank account for accounting purpose.If you need help implementing systems I also have a consulting business so feel free to connect with me and ask me anything or if you need some one on one coaching.

What worked for me to find contractors in my area was first finding a HUD consultant in my location through the HUD Website. 

Ideally you'll be consulting both a business attorney and a tax CPA/EA to get both sides of the coin before any actions are taken. 

Consult your insurance agent to get real numbers. 

This will allow them to sell their Hawaii property tax free, or close to it, because the $400k loan will reduce their gain when they sell.You'll want to consult a mortgage expert and tax professional, since I am neither

Always consult with your attorney before you rely on the above information.

Contact a local architect/engineer for a detailed consultation specific to your project/locale.

Hire a consultant that is familiar with your project type, that can help guide you through the process.

In California, I think that's $70 upfront and then $800/year/LLC (again, you'd need to consult a licensed, practicing attorney in CA to confirm what I just googled about California).