Do I simply need an inspector to come out and verify the work was done to code?

They have a code of Ethics they agree to follow and can be sanctioned by if a potential violation is found.

The systems (electrical, plumbing, HVAC) are compliant with the latest construction codes.

However, at a higher level based on my PA knowledge which I assume is similar to TX:PA's municipal planning code grants building code and other enforcement authority which would cover all of the items you mention in PA. 

I also have a specific borough in NYC that I consider my farm, but I'm not sure if that's specific enough so I've been mainly looking at a specific zip code.

But one of these days i will crack the code and start making some money with this.

I suspect two things1. overall lot size is too small and not conforming2. width to length ratios won't meet set back codes as you mentioned.value is to the owners on either side...I sold my Jenner lots last month.. after trying to perc them for 11 years LOL..

Code enforcement(disgusting living conditions), the city?

I will get on my laptop in about an hour.

(Code violation back here.)