Best Practice on local use of Private Field x Property

Question

When inside a class you have a private fiels and expose that field on a public property, which one should I use from inside the class?

Below you is an example on what I

Answer 1

Use the private field because you are not doing something in specific in the setter.

I would also recommend to remove the property-setter, this way you force the state of the counter to be set by the given method DoSomething()