The "owner occupancy eviction" thing is in the ether because that's part of NYC regs, but it's not legal here in JC, and I don't believe in NJ at all.

Hello, Should I start a legal business in order to start investing in real estate ??

I can't really speak into the actual legalities and logistics of it all just b/c I am not well versed in it...however, I did learn a lot about how it functions just by reading up on the lawsuit files that are posted publicly online.  

Is it legal for homeowners to sell the property without me knowing?

I wasn't sure if that was legal, let alone possible. 

If the building has a single legal address most of our carriers would consider it to be one building with two units.  

Last week, I received a Legal letter (from a lawyer) that I owe $2500 dues in HOA and requesting to pay it and failure to pay will result in lien on the property.

first position is always best... and fractionalized mortgage interest or DOT interest are legal in many states.. in many states like Oregon for example its not legal to have multiple beneficiaries.. without doing a real estate paper offering ( mini PPM).. 

While it might technically be legal, it would set off all kinds of red flags for the next sale.

I know in general wholesaling can be legal, but from what I understand and have learned, it's a very extreme fine line.