Can someone recommend a trusted expeditor in Brooklyn (Kings County) who knows how to navigate the system and help me clear the violations.2.

You will learn things you could never have expected, and 90% of tenants are happy and willing to discuss, and maybe even show you some things that will help you out later. 

Hope that helps. 

I believe you guys can help me.

@Josh Banwart happy to help, and I would recommend reaching out to @Marcus Long as well.

If you are starting out, Clever Summit has very affordable tickets and will help start networking with others.

So far I've learned of 3 services that help with both: Rently, Showmojo, and Tenant Turner.

When you meet with the contractors, make sure to have them help you understand what you have, what will be required to repair and maintain what you have, and what you should be budgeting for future capital improvements, if needed.As we go through DD, we are also putting together the strategy for the park, performing our rent survey, running our test marketing to understand the demand in the market, and creating the budget for the project.All the best,Jack

Tenant income helping pay down my mortgage?

You'd likely need some help navigating the short term rental permit process.