I wouldn't run, I'd just make sure there's no active infestation and that it can be repaired.

If the inspection did not reveal active infestation, it may be a non-issue as long as the header is still functioning as intended.

We were told this solution was arrived at after a decade of silver fish infestations and excessive clogged sinks and toilet overflows.

Mouse infestation due to food all over the home.

I agree this is shark-infested water.

Another tenant in a duplex that I kicked out (inherited tenant) because they infested the whole place with fleas ...like serious horrible fleas that had to be sprayed 4 times to treat after they moved out.....from their dirty smelly dogs ...that smelled like dirty dog the first second you walked through the foyer and they had a horrible dangerous dog that was vicious & large and go after repairmen or anyone it saw.

You do need to be aware where the drug/gang infested areas are. 

It isn't obvious visually to know where the crime infested areas are. 

If pests were not the issue 3 months ago then they might have infested after your arrival.

I found myself many properties that had beautiful paper returns but would require managing destructive tenants, crime-infested areas, etc to get that return.