Buying a house with original septic system to flip

[Nelson Del Castillo]

I am looking to buy a house with the original septic system. I already know the tank is bad and needs to be replaced, the leaching field could not be easily checked being that they are deep under ground... would you stay away from a house with a septic system this old (house was built in 1972) ? Would you assume that the system is automatically going to go any second because of its age? Comparing this same house apples to apples to a house that has city sewer and city water, would the house with septic be worth less because the system is 50 years old? What are your thoughts?