My parents live in a bungalow which they extended upwards into the loft area. Upstairs they now have two bedrooms and a smallish bathroom with walk in shower (no bath). The stairs up to this conversion are quite steep, however they currently have their bedroom up there.
Downstairs is a further bedroom and what I would call a 'family' bathroom with a good sized bath with decent shower over it.
As my parents get older (they are already both mid eighties but quite spritely) my dad is concerned that as they age (!) they may find it more difficult to get upstairs so is considering ripping out the bath downstairs (difficult to climb into even to use the shower) and replacing with a shower cubicle.
However if they come to sell, as it is a good sized house it would probably sell to a family, so he is not sure he should be removing the only bath the house has. But if the plumbing is already there it wouldn't be difficult for a new buyer to replace a bath would it?