you have 3 days unless you negotiate with the new owners. Also, moving after the trustee sale is tricky because essentially everything in the home now belongs to them. It's smarter to move out before the sale.
Ownership and possession of a property do not necessarily change at the same time. You could rent (or lease) the house from the new owners, if they choose not to occupy the house after they purchase...
It should be specified in the papers - but the minute the lienholder takes legal possession of the property you no longer own it and are subject to eviction at any time.
You will need to find a new insurance company and purchase a "Vacant House" policy. These policies are "fully earned", in that if the house sells you will not get a refund. Policy generally must be...