Repairs to old cottage

Hi,
I currently have 1 residential investment property that is rented - Very little capital allowances / mortgage interest to offset against rental income - once the mortgage repayments / annual charges / Insurance / Property tax / Rental income tax, there is no surplus.
My family have a cottage that has not been lived in for many years. With some investment, it could make a nice family home for someone. Its quite rural. I have contacted the local county council a number of times regarding the repaid and lease scheme - however haven't even got a response.
My question is. If i complete repairs on the cottage circa 70K - 100k - are these repairs off-settable (in terms of tax) against the total rental income for both properties? of just the property that is being repaired? I am looking for a way to avoid letting the cottage fall down & possibly by leveraging the rental income from the existing rental property.
many thanks

The costs of renovation cannot be off-set against rental income even from the property itself. Sorry!

If the property has been vacant for some time it is likely considered derelict. Is the property tax being paid or was it declared derelict to avoid this?

If it is derelict then full planning will be required to bring it back into use, and that may mean a significant investment to bring it up to the current building regs. Speak to the planning dept, in your local authority.