You can find romex tied onto knob and tube, behind a wall with no junction box; or cast iron waste lines corroding from the inside to a point where they have long splits leaking very slowly in your walls; or galvanized, and even lead, pipe sections in difficult locations; and of course the exterior supply and waste lines are often ignored until they can't be.

I would never think about what kind of piping in house iron cast or PVC.

Also, to your point, strike while the iron is hot.

I valued my life in that tense situation and chose not to force my way in (ironically with law enforcement present). 

Iron sharpens iron.

I just had a Duplex re-piped in Murray Hill, the property had old cast iron pipes that went from the 2nd floor bathrooms into the first floor kitchen and down into the crawlspace under the property.

The water in the city where my apartments are located is said by area plumbers to be "good water", not full of iron or other minerals that might cause water heaters to go bad quickly, and that seems to be true since the old water heaters lasted so long.I've had an area plumber tell me that all tank water heaters in the US are manufactured by the same three companies (Rheem, A.O.

Capital cost is usually higher for shorter terms, but with these types of loans you can strike while the iron is hot (usually <14 days to close) and maximize your ROI.

If the supply pipes in the wall are old, especially iron pipes, you may have bad threads at a joint that are leaking slightly.

Cast iron piping is leaking.Roof is in need of repair within 5 years.Electricity needs updating eventually (cloth wiring, knob and tube)Otherwise only small nickle and dime fixes.