Complete dump-cost to rehab?

[Mary Jay]

Ive always thought that if I buy a completely dumpy house it will cost me 100K to rehab it. (Sort of like in the show "Good Bones") 

But people on this forum told me it should not cost that much on a 1000 sq house...

So how much would you say approximately it cost to do a complete rehab if a house is a  dump (just like what they deal with in the "Good bones" show) But my house would be smaller than theirs, mine would be lets say 1000 sq feet

I know it is hard to tell the exact number, but can you please give me a ball park? Lets say that roof, siding and foundation are ok.. Only inside needs to be gutted (new electrical, new plumbing, new flooring , the cheapest flooring) Can you guys let me know approximate numbers?