Developer Deposit Refund Negotiation

I need a skilled negotiator to help me get a refund of my deposit from a developer. I attempted to buy two flats off-plan, but the deal fell through due to the developer's delays. The deposit amount is in the region of £35K... (Budget: £250 - £750 GBP, Jobs: Contract Management, Contracts, Legal, Legal Writing, PHP, Property Management, Real Estate, Real Estate Management)