I've used this strategy to acquire over 400+ Airbnb's in under 12 months. 

And I’d be able to pay off the remaining pretty easy in under a year.

And instead of paying it off in 25 years you're paying it off in under five years.The reason the ninja trick works so well is because you set up your HELOC as your primary bank account.

The main house appraisal came in under the contract amount so I have an out that I'm considering using.

If they say above 20% in under a year...RUN!!!!

All in all, if you can buy a home, rehab it, sell it and close on it in under 90 days you are a champ in my book.

You can find it here: How to Create an Awesome Lead Generating Website in Under an Hour with No Technical Abilities

I started investing in rental properties last February and have scaled my way up to 7-doors in under 6 months.

The law is basically 10 days(they can't file a complaint in under 10 days from when you are notified of a problem), and you're in NYC, you should have no problem renting to someone else if she decides to leave. 

@Kalen Mills I own 3 rental properties that I hold title in under my LLC, so I can have some extra liability protection, but does not really help me for tax purposes since I am the sole proprietor of the LLC.