When I crunched the numbers it wasn't worth it, and even the thought of trying to get financing with the knob and tube electric and dinosaur furnace gave me a headache.

He filled the entire tube.

My electrician (who I have used on a dozen jobs) charged me $250 to replace knob & tube wiring to two outlets with an open basement.

How old do the dirt tubes look?

Not to mention lath and plaster walls and knob and tube wiring and old plumbing.

A culprit I'm cognizant of is the toilet overflow tube and fill valve.

It may be helpful:Here are some things to look for from an Insurance prospective:1.Any in-ground tanks (active or inactive)2.Any Knob & Tube or Aluminum Wiring3.If built before 1978, does the building have Lead Safe certifications4.Any wood stoves or secondary heating units.

They don't know whether the subject property or comps have knob & tube wiring, popcorn ceilings, cedar post supports, ancient plumbing, rust inside the electrical panel, floors that are out of level, foundation defects, termite damage, a failing septic system, well water that smells like rotten eggs or any of a thousand things that could drastically change the home's value and most of which are impossible to pick up from listing photos or tax records.They also don't know neighborhoods. 

So I thought this was a porn thread. 

You may have old knob and tube or not.