Expenses while waiting to sell are much more complex than during voids. There are a few things you need to consider.
First of all the rules on revenue vs capital are the same. Capital costs are always allowable against the final sale value so there are no changes here. If prior to sale you add a conservatory then the cost will be part of the capital gains calculations.
Revenue costs are different. They could be allowable but only if there is a continuing rental business. So if you have half a dozen properties and one is empty ready for sale then the revenue costs will be allowable.
If you are selling your last property then once you decide you are not letting any more the expenses will not be allowable against your rents. Your next logical question is probably whether you can offset those revenue costs against your capital gains? No.
Part 3 will cover empty periods in holiday rentals…