@Omar Fernandez - you can start by reaching out to some attorneys, NYC is an attorney city so you'll have to get an attorney involved (who usually orders the title search). 

It's vitally important to know who you are working with, and have the history of the players involved.

It’s crucial to ensure that you’re compliant with local zoning laws and HOA regulations related to vacation rentals, as these can affect your ability to rent the property.Overall, while it can work well, especially if you're looking for income from rentals, make sure to have a clear understanding of the financing rules, potential restrictions, and the financial risks involved.

If you prefer long-term stability and future appreciation, White House may suit you better.

@Christopher HeidrichRecommend you first figure out the property Class you want to invest in, THEN figure out the corresponding location to invest in.Property Class will typically dictate the Class of tenant you get, which greatly IMPACTS rental income stability and property maintenance/damage by tenants.If you apply Class A assumptions to a Class B or C purchase, your expectations won’t be met and it may be a financial disaster.If you buy/renovate a property in Class D area to Class A standards, what quality of tenant will you get?

@Fred Robertson, I was actually reading a little about this sort of thing today and it is absolutely the kind of thing where you get a CPA or certified financial planner involved!

Thank you Jaron..really do appreciate the guidance and candor…I am probably not articulating the finer points well…my daughters are actually only the tennets…they are not involved in any of the potential decisions I am considering.  

You might find that the stock market makes you more money with less work (seems you are trying to minimize your involvement w/ the rentals). 

When investing in high cash-flow markets, I always recommend working with an investor friendly agent so you're able to gain the right insight on the different areas and the risks involved.

If your sister-in-law prefers not to be directly involved, your wife could become the sole owner of the LLC, and your sister-in-law could be given a secured interest in the home after the HELOC is obtained.Additional Considerations:You mentioned owning two other properties.