I have been using the BIS site, and as Llewelyn mentioned, the Dept of Finance tax code is 2 family, but no CofO from DOB to support. 

Our city code requires a method of egress for 3rd Floor units.

Requiring a real estate license can potentially be a “trap” for wholesaling, as real estate licensees may in in violation of their code of conduct by way of their wholesaling activities.  

You are subject to new building codes.

But you will want to change the code for access right away as fired contractors can come back and take materials from you for other jobs.

I think if you understand the price per unit as well as the price per square foot in the zip code and nearby zip codes that will give you a good idea of the comparable market analysis approach and appraiser might use.

Be sure to review property tax statements and verify any zoning or code compliance documentation.

We live in a very intersting, diverse, and complicated market and understanding the intricacies is very important - especially for a new investor.Markets in the same zip code even have their own submarket and tendancies depending on location and its important to look at things hyperlocally in philly.

Example: I define what zip codes (or neighborhoods) that I buy in.

What ghetto city/zip code in AR did you find 2% rule?