|Sculpture on the grounds at Columbia University, NYC|
Not being able to clearly identify the beginning and the end is fine in the world of art and I'm sure in many other "places", but it really makes life complicated when professional services are being rendered or offered. Most professionals - and their clients - can tell you with some certainty when a professional relationship began, but all too often there's nothing quite so clear when it comes to the end of the relationship.
Law firms, and some other professionals, use engagement letters when signing up a new client, and they use (or they should use) dis-engagement letters when firing a client, or when the client takes their business elsewhere. Not doing so is simply an open door for misunderstandings, and unfortunately these days that could spell trouble. And trouble in this case is spelled l-a-w-s-u-i-t.
If your clients are providing professional services and not using written contracts they're asking for problems. It may not seem like it has anything to do with their questions about insurance, but if your client is still doing business in a very informal way, especially if they have some assets at risk (and they do), it would be wise to encourage them to be a bit more proactive. And by advising your clients accordingly you will be helping your own agency avoid potential errors and omissions issues.
There's a very good post about this by a law firm called Goldberg Segalla with some case study info provided. Here's the link http://professionalliabilitymatters.com/2013/06/05/the-break-up-knowing-when-the-professional-relationship-is-over/
It would be nice to think that the world still functions as it did "back in the day", but as we know things have changed and not always for the better. If you need some help finding resources, making suggestions to your clients, etc just let me know. I'd love to give you some tools to work with.