Hi There if you look at HMRC manuals you should be able to include the expense in the first year of letting on the following basis:-
see
http://www.hmrc.gov.uk/manuals/pimmanual/PIM2505.htm
A taxpayer may incur expenses for the purposes of a rental business before that business starts. If so, they may be able to claim a deduction for them once the letting begins, (ICTA88/S401 or ITTOIA05/S57). Relief is only due under these special rules where the expenditure:
•is incurred within a period of seven years before the date the rental business is started, and
•is not otherwise allowable as a deduction for tax purposes, and
•would have been allowed as a deduction if it had been incurred after the rental business started.
This means that, to be allowable, the expenditure must be incurred wholly and exclusively for the purposes of the rental business and must not be capital expenditure etc (see PIM2000 onwards)