As well as the legal fees and any possible searches, it is likely that there will be extra third party expenses with any Leasehold Transaction.  For information click on the type of transaction:

    Expenses on the purchase of a property with an existing Lease
    Expenses on the purchase of a property with a new Lease 
    Expenses on the sale of a Leasehold Property
    Expenses on the extention of a Leasehold Property