It is not unreasonable for them to contact the neighbor but it would probably be a difficult task to get the neighbor to respond.

Can you provide guidance on how to get started and some effective strategies?

There's nothing you will be able to do unless the heirs agree to go through probate to get ownership of the property and then sell it to you.

@Dhruv Patel I believe you are getting ahead of yourself....Where in the US are you all-in (land acquisition, soft costs, hard construction) on new construction multi-family for $100/ft.

Each program is a little different so it just depends on your situation and income.They are quick and easy though once you get your certificate you can work with any Bank or Lender that is approved to use those DPA's.

Challenge is where is their motivation to properly screen applicants and get rid of nonpayers?

With you managing their properties for them, it gets more difficult to meet this test.  

Imagine a 4bed/2bath home with a small ADU in back, a converted garage with a private entrance, or a three-level home with a basement that can be converted into a private apartment.You can get privacy and house hack, but it takes a little more effort.

Do you plan to get a job in NYC and network with your co-workers?

We paid off our primary home last year and have been slowly getting the courage to jump into the investing market where we live in the Pacific Northwest.