I am afraid that there is no legal aid for this.
However if you need to go to court, you can probably get the fees for the court application waived.
You need to write to your parents telling them that unless they let you have your belongings back (the papers) by next Friday, 23rd of March latest, you will make an application to court for an injunction to make them give you the items back and you will ask the court to award costs against them.
By the end of Friday, you haven’t got the items back or they haven’t agreed to let you have them back, then you make the application to court to compel them to give you the documents and other belongings. You need to complete court forms N1 and N16A (Google will provide) and you need a witness statement in this format in support of your application: https://www.justice.gov.uk/courts/procedure-rules/civil/standard-directions/general/witness-statements
The court application fee is £255 but if you fit the criteria, you can get this waived. Here is some reading on that:
What you can’t do causes your parents with a blunt instrument until they capitulate and give you your belongings back and if they won’t let you have them, your only remedy is to threaten court and ultimately take them to court.
A solicitors letter may remove the need to go to court but they are unlikely to let you have one unless you pay.
Can I clarify anything else for you?
I’m happy to answer any specific points arising from this.
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