I bought a condo on a 100-year flood plain back in the day.
Had 2 100-year floods, the first 2 springs I owned it.
A million year asteroid could hit almost literally at any moment.
Yeah, not really. With the current state of various spaceguard projects working on mapping NEOs (near-Earth objects), the estimated "heads up time" for an extinction level asteroid impact is on the order of decades. The smaller the object, the less notice we get, but the risk also decreases dramatically.