If you truly want professional advise to confirm what the other forum is telling you, or to assist with your own research, I would suggest paying for a consultation with a CPA rather than relying on that of a free/public forum. 

I want to thank Rent To Retirement & Zach, who got me a free consultation for.The costs to do this do reduce cash flow as well as the administrative time to file the different returns/reports are real, but it is worth it to reduce liability for the long term. 

Additionally, income from an active business inside of a retirement account will be subject to UBIT (unrelated business income tax), so be sure to consult with a qualified tax professional about the implications. 

But I would consult with a CPA that specializes in STR.

Another option is to find a good local architect, civil engineer, or similiar third party consultant to take a look at it and let you know their thoughts on the viability of developing it. 

As Brian emphasized, consulting with your legal team is crucial in such matters, 

Consult your tax professional.  

Consulting with a real estate attorney and a tax professional will help navigate the legalities and optimize tax impacts of owning a rental property in your chosen location.

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

If you are not sure regarding notice wording, consult an attorney.