You can expect pretty much what you see on this site. We would be grateful if you would post to the Q&A board the name of the lender and the collection agency and the telephone number your family were asked to ring.(posted 8586 days ago)We'd also very much like to have copies of the letters they have sent to your family to publish.
What you should do depends on your circumstances. You should read the Repossession section, and especially the Dos and Don'ts seciton to get a feel for this.
Lee