Home for sale with undisclosed swat team raid including tear gas

[Nathan Thompson]

I'm looking at a house for sale in Colorado that has an assumable 2.25% mortgage. The PITI payment is $2600 on a $430-450k original mortgage. I looked into why the escrow was so high and found it was due to high insurance costs. I live in the area and it's not a wildfire, flood risk, so it didn't make sense. Also, there were strong air fresheners in every room. Eventually I found out that there was a SWAT team raid about 7 years ago which included tear gas canisters.

We had already asked about the insurance costs and the agent tip toed around it and never gave an answer. We're not sure if it's been remediated, but it looks like the cost can range from $2500 to $25000. I'm assuming it was either remediated and claimed on insurance, or that it wasn't remediated, but insurance company found out that there was a raid and jacked up their rates. 

Is this something that's legally required to disclosed given the hazardous nature of tear gas?  

If insurance costs are higher due to the raid, is that something that stays with the house or does it stay with the owner?  Should I expect to have high insurance costs if I buy the house? *I'll ask my insurance broker if we decide to pursue. 

Trying to get a sense of what to expect and if it's worth continuing.