The Telmessos and Marcan hotels are at the top of a very steep hill. As dad is in a manual chair we took turns pushing him up it (going down we just let him go
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)
The rest of Hisaronu is on a slight incline, but is not particularly hilly.
I have seen lots of people in wheelchairs there and it is doable, but you shouldn't expect the hotels and restaurants to be *as* disabled friendly as the UK.
There are lots and lots of bars and restaurants on the ground floor of buildings so you don't need to worry about not being able to eat - there will be plenty of choice for you.
It may be worth calling a tour operator and seeing if they can recommend any disabled friendly hotels (with wider doors to the loo). You definitely would not be okay in the Telmessos. Dad had to collapse his chair whilst sat in it to get through the bathroom doors! The actual doors to the rooms and so forth were fine though, so it may just be that that particular hotel has small bathroom doors. He didn't have problems in any of the restaurants we went to.