Ladies of a certain age have often asked me to fit a doorbell that they have just purchased. My heart sinks when they hand me a wireless bell, because I know they will soon be back on the phone saying "That bell you fitted isn't working". I dont care if the manufacturers claim the bell push is weatherproof, going from past experience, most of them aren't.
As a rule there is only one bell I would recommend ... it is easily fitted by a handy person and it has propably been around in it's same form for at least 40 years. It is battery powered and rings like a fire bell. Over the years I have tried to convert owners of troublesome wireless bells over to it... it is called a 'Friedland bell in one'.