You are smart to not just take a realtors word for it, as they effectively have no real liability if it isn't "fine".  

Hi,I am budgeting for the basics for my NOI (and taxes, insurance too):1.

The requirement to defer all tax is simply to purchase at least as much as your net sale (in your case 50% of the net sale of the entire property). 

If they tell people to only put cameras in specific areas and the property owner gets caught breaking the rules the renter can make a case that Air B&B has some liability in the matter due to "lax indoor camera policies" or "not enough oversight".

Rental property owners, did you know you can deduct expenses like mortgage interest, property tax, operating expenses, depreciation, and repairs?

The clause is: ”Indemnifying and holding Broker harmless from and against all losses, damages, costs and expenses of any kind, attorney's fees, and from liability to any person, that Broker incurs because of acting on Buyer's behalf”I haven’t seen anything like it before.

Tax BenefitsWhen buying in low cost areas, it can be difficult to achieve FIRE without high volume of units.

And there's the unpaid taxes for operating illegally... i'd give this property a thumbs down.

Each year being worse than the one before with higher insurance, property taxes and wages?

(Someone to receive notices on your behalf)Residential income properties need a Transaction Privilege license in most locations (Rental Tax)Property Management is a specialty in the industry and it's very possible your sister has her license with a broker that doesn't allow her to do property management?