Generally, when a person places an order for something, like a service, and pays a deposit they enter into a legally enforceable contract with the other side. It is implied that the service provider has accepted the deposit as security and as proof that the buyer wants to proceed with the contract.
Unless you subsequently commit a serious breach of contract, or there was a cancellation clause, the consumer would have no legal right to cancel the agreement and if they do so they will be acting in breach of contract and risk losing their deposit. This is especially true if the deposit was described as non-refundable.
However, you will be subject to certain consumer rules and regulations. For example, the consumer will have some protection under Schedule 2, Regulation 1(d) of the Unfair Terms in Consumer Contracts Regulations 1999. It states that if the contract has been cancelled after a deposit has been placed they are entitled to have the deposit returned in full, unless you had spent time, effort and money, in which case you can deduct reasonable expenses. Even if some expenses have been incurred, if these are subsequently recovered, for example by selling the services or items to someone else, the deposit should still be returned in full. It follows that a blanket non-refundable clause that entitles you to keep the deposit in all circumstances is most likely going to be unfair and unlawful. However, you are able to retain the deposit to cover for any losses you had incurred as a result of the cancellation, assuming you had no opportunity to recoup them.
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