if the walls are wire mesh enforced cement /or plaster then you should be able to get away with molly bolts, but I personally would shoot for a stud for a grab handle. if your going to remodel in the next year I'm sure you could survive some caulk plugs in the holes for the missed the stud search.

I know a lot about a lot of things BUT I still have a lot to learn.
Life is what you make of it. So, why not make a working machine to make it easier.