I have a client with an overpayment of IS the reason for this is a living together decision. The client states that her partner stayed only 1-2 nights a wk, I was looking for clarification on how often a partner can stay or is there any authority that I could us to help me with this issue.

Depart also have proof of post going to her address, is there any authority on the use of a corresponce address?

There's no cut and dried answers to your questions - see page 704 to 707 of CPAG as a start.

Nicky

Does he have another home where he lives more of the time, or is he essentially no fixed abode and finds it convenient to him (if not to her) to pretend tothe owrld he lives at her address to do things like get credit and insurance?- not an unuusual scenario, in my experience.