Thanks for your enquiry.
I am afraid to say that from a legal point of view, you wouldn't get very far at all in taking your sister to the small claims court. This is because the fees you incurred were your own and nothing to do with your sister.
Upon agreeing the price of the transfer of the property to you, the price you agreed to pay should really have taken into account any costs you were to incur. As such, the only legal agreement you had with your sister is that she was to receive £x from you in return for her transferring the property to you, and any costs incurred by you in fulfilling this would have been your responsibility.
I am sorry this is not the answer you were looking for, but it set sout the legal position.
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