Can I set up a default method argument with class property in PHP?

Yes, you have to do it this way. You cannot use a member value for the default argument value.

From the PHP manual on Function arguments: (emphasis mine)

A function may define C++-style default values for scalar arguments. […] PHP also allows the use of arrays and the special type NULL as default values. […] The default value must be a constant expression, not (for example) a variable, a class member or a function call. […] Note that when using default arguments, any defaults should be on the right side of any non-default arguments; otherwise, things will not work as expected.

You absolutely can do this. Best of both worlds: initialize your default property AND your method's default argument with a class constant.

class Object {    const DEFAULT_BLNOVERWRITE = TRUE;    protected $blnOverwrite = self::DEFAULT_BLNOVERWRITE;    public function place($path, $overwrite = self::DEFAULT_BLNOVERWRITE) {        var_dump($overwrite);    }}$Object = new Object();$Object->place('/'); //bool(true)

You must do it that way, afaik, or use a class constant since php 5.3 but of course its fixed and cant be changed later so i would definitely go with your own solution:

class foo{    const constant = 'bar';    public function place($path, $overwrite = self::constant ) {         die('bla' . $overwrite);    }}$bar = new foo();$bar->place('baz');