The building has been approved for a 4th unit in the past but was allowed to lapse and would need renewal. 

They are going through a divorce and they have let things lapse.  

You can and may require that tenants list you as an "additional interest," which would give you notification of cancelations, lapses, non-renewals, and renewals.Additional interest doesn't provide you any coverage, of course, beyond the liability coverage on the policy, but it certainly puts your mind at rest.  

You are notified by the insurance company if insurance lapses.

i remember a tenant on housing assistance lapsed on their electricity and housing assistance terminated the agreement - not exactly apples to apples but a data point

I also have an abundance of detectors of both types, and I hardwired them so no lapses from forgetting to change batteries.

I am assuming that ship has sailed by now since you are close to closing but something to think about for the future.Contact a lawyer and see what the best way to go about evicting a month to month tenant is in your state.For instance, in CT it is much easier to evict for non payment of rent as opposed to lapse in time.  

Lapsed Catholic :-)  I've been grumpy lately and I shouldn't be taking it out on people on the forum. 

Our board let the FHA approval lapse right when we decided to sell, so all we could hope for was a 20% down conventional buyer, so we dropped the price a bit and found someone who qualified with that.  

This will notify you if there is ever a termination, cancellation or lapse in the policy.