Appears that 'your' car is registered in your Daughter's name (and at her address?), so finance is also in her name / paid from her account? In which case nothing to do there. How is it insured? You might have to change over the policy, at least you will need to advise them of change of plates. If not reg at her address then on-line change of address for the V5.

For S-I-L's car, can be done on-line, register the change of keeper, then you can tax it (and he will get refund for remaining tax). You can also apply on-line to transfer the plate from your car to his, which will trigger a new V5 for your car. Change over the insurance and away you go.

Make sure you only use the official DVLA website and don't pay any fees - anyone charging is just a postbox and charging a fee for no reason.

www.gov.uk/change-address-v5c

www.gov.uk/sold-bought-vehicle

www.gov.uk/personalised-vehicle-registration-numbe...f

Thank you your information.

Yes everything is in her name address. The money comes from her account. I insure the car and private plate in my name and address.

Kind regards

Private plates don't belong to anyone except DVLA - the registered keeper of the car has control of putting the number on retention or transferring it to another car.