The best place to start is by googling what that areas regulations are for 3 family properties.

And that’s not even getting into the details of what happens if you have LLCs in multiple states, each with different legal regulations and tax obligations.

In some areas, rents increases are limited by local regulations.

@Matthew Meade look into the laws for short term rentals and taxation before you start up rules, regulations and taxation vary greatly from city to city

That is regulated by the SEC and the CA regulator. 

BUT I would guess if you don’t have a license there’s no one who’s regulating how you screen your tenants and you have free reign.

ESA are not considered petsif the ducting was free of pet dander at move in, charging for the duct cleaning due to the ESA is a legitimate cost of the ESA and is allowed to be passed on to the renter.Consider using a pet screening service such as www.PetScreening.com (no affiliation), it can discourage some unscrupulous tenants with ESAs.My view is HUD should change their current regulations regarding ESA to reduce the abuse. 

Hey mate,The US market is a different world compared to back home.After 500+ deals under my belt, millions in profit and losses I have concluded that "business is easy and people make it difficult" lolThe real estate professionals here in the US sometimes tend to be very unprofessional unlike in Australia.It's more regulated there especially when it comes to property management.My best tip would be to take your time and don't jump in.There is no rush and the US is full of deals.Spend the time in doing due diligence more so on the people that you are looking at working with rather than the stats/demographics of a particular area.I wish you much success 

If you are soliciting from people you do not know; i.e. they are not friends and family, then you're going to have to study up on the SEC rules/regulations for soliciting money for real estate.  

If you are in a neighborhood that has a strict HOA or other regulation on Airbnb and vacation rentals but you choose to do it anyways then you may be breaking the law.