Boxes are always stacked on top of damage. 

If a house had fire damage and an investor e.g. myself remodels and brings it up to code, when I flip, do I disclose to the buyer that the house had prior fire damage ?

It had sat on the market a while (Likely because the pictures taken were sub-par and there was minor damage to a detached garage.

No stains on the carpet or damage to anything.

Since the Municipality has separate Lot and Block Numbers for all three parcels, and taxes them using those Lot and Block Numbers, I don't understand why the County Clerk is unable to find them in the County database.This is an interesting situation and I will keep you updated.

A few years ago if a tenant owed you rent or damaged your property you could enter the premises and “hold” certain items.

They're new items but have minor damage or are recertified.  

They are building a new town center at the corner of my block (literally) with over 1300 new apartment units, 250k sq ft of office, and retail space.

I'll be looking for areas where I can rent the property out to white collar or stable income families who would be paying rent responsibly and not damage the property.Also areas should have cash-flow positive.

A few things you should know about the market, Philadelphia is extremely block by block, my office is in Northern Liberties where there are 600-700k houses, and a short drive north, and your in the drug capital of the city.