Now is the time to strike while the iron is hot in order to be in on the ground floor.Thoughts?

For example, some close friends lived in a 1940s home as their primary residence and had a terrible time with cast iron pipes, and because of it are firm that if this house has cast iron, they’d walk.

The property is zoned CMX-2 and is by right allowed to have 2 residential units and one commercial (min first 30' of frontage).The inspector who came yesterday to okay closing up the walls said that for the commercial unit, which is the front half of the first floor, there are more significant drywall needs for fire purposes, and we also need cast iron & copper plumbing versus the plastic that's already run AND used throughout the rest of the property.A couple years back there was a big change in plastic vs. metal for plumbing in Philly, but I believe that may be specific to Residential.Really curious for any feedback on this.

Most plumbing will be cast iron and it simply is what it is. 

In the picture where you can see the gutter/white down spout, that at one time would tie into the cast iron (guessing its cast) pipe hidden in the picture behind the white down spout. 

Not sure this was what you were going for, but I proactively remove any accesable galvanized supply pipes (replace with Pex)  or cast-iron drain pipes (install extra cleanouts) I replace all fixture shutoffs to quarter turn ones. 

Ironically, that also makes it more costly to stay part time - a full time agent can choose to only work in one, or perhaps two, of the jurisdictions and forgo the expenses of the other license(s) more easily. 

They do recommend replacing cast iron pipe to clay for this portion.I am looking for your input based on experience on the following items:1.

More that I just received:At this price, we're practically giving it away...100% Iron-Clad, Money-Back GUARANTEEHere's a blog link where the comments offer some explanations on the guru mindset and operations:http://realestate.bryanellis.com/1167/why-i-wont-participate-in-product-launches-with-the-gurus/

Iron pipes corrode from the inside out, so you often are not aware of problems until they do leak, or even burst.