Thanks for your question.
Check the tenancy agreement your daughter had, in all probability it will state that it is an assured shorthold tenancy.
If you are (occupying on an AST) then your landlord must put the deposit monies in to a tenancy deposit scheme within 14 days of receipt. All deposit under ASTs have to be placed in such a scheme and you can sue the landlord for the return of the deposit and a fine of three times the amount of the deposit if it has not been placed in a TDS.
Similarly when a tenancy comes to an end the return/deductions of the deposit would be made through the scheme. If this has not been done then it suggests that it was not placed. Ask the agent, if the landlady is no longer her client then they may give you information.
Ask for details of the scheme in to which the deposit has been placed. If the deposit has not been placed in to a scheme then she can either write a tersely worded letter asking for the immediate return or issue a claim for the above monies and fine.
If it has not been placed then she will get judgement, the question is whether the landlord has assets because judegment is useless without assets/income to enforce it against. Repossession does suggest financial problems obviously, but she can issue the claim herself via http://www.moneyclaim.gov.uk/ fairly cheaply.
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