heads up for 1st time investors

So i finally got my 1st rental property , i used a small bank to fund the deal after my mega bank refused to fund it ( too small for them) ,,

i did not read or heard this before till about to close on the deal . since it's a rental property i had to show my insurance a signed lease for the property before i closed on it ..they will not insure a vacant home ..and my bank will not close the deal till i did that ...

is this a insurance company thing or that's the standard