Hello, thank you for the question.
I am a UK qualified solicitor and happy to help.
I would agree that 2 years' rent is reasonable in the circumstances which you describe and cannot see the company being obstructive. If they are, I would send them a letter before action to demand payment within 14 days and say that if they do not pay you, you will issue county court proceedings against them. See attached template as an example of what to say.
You would then need to register at www.moneyclaim.gov.uk so that you are ready to issue the claim in the event they dispute the refund and do not pay you. The website is very user-friendly and you would not need a lawyer unless the claim is worth over £10,000. All claims under £10,000 are classed as a "small claim", so legal costs are not recoverable and the matter would be dealt with on paper by a Judge, not at a hearing.
You would claim the sum for the refund, the court issue fee (details of fees are here: www.gov.uk/make-court-claim-for-money/court-fees) and court interest which is 8% calculated on a daily rate from the date of loss to date of court judgment.
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