I don't' see what the basis (adjusted or not) has to do with claiming property improvements and repairs. First, repairs are a deductible expense in the year incurred. Period. They get reported in the rental expenses section.
Property improvements add to your cost basis. Property improvements are entered as physically separate items in the Assets/Depreciation section.
There are some types of property improvements that, if they cost less than $2,500 they can be expensed. But again, that has nothing to do with the basis of the property. You don't have to determine it, in order to claim the property improvement either as an asset if required, or as an expense if it qualifies.
