This is a common difficulty when calculating net rental property income and you should really seek advice.
It depends on what the expenses were and when they were incurred.
You can claim for maintenance and repairs/renewals. Repairing or replacing should be ‘like-for-like’ as much as possible (there may be no modern equivalent to the original item) but you cannot claim for repairs that constitute an improvement to the property. e.g. You may make a claim to replace a bath but not for installing an extra shower unit.
You can also claim for repairs incurred in preparing the property for rental. Pre-letting expenses are treated as incurred on the first day of rental. Repairs incurred prior to the ‘decision’ to rent the property are not claimable.
Since April 2016, you can claim for replacing furniture and white goods in a rented property – but not for the original furnishing of the property.