Where Netbeans can’t guess the type/existence of a local variable, you can tell it in a multiline comment:

/* @var $varName TypeName */

After this comment (and as long as TypeName is defined in your project/project’s include path), when you start to type $varName, Netbeans will offer to autocomplete it, and will offer TypeName method/property suggestions. If you rename the variable with Ctrl+r (rename refactoring), Netbeans will change the comment, too.

I usually forget this syntax because type comes first in @param declarations.

Update: PhpStorm supports a similar syntax, but reversing the type and variable name:

/* @var TypeName $varName */