regex - UTF-8 encoding for Yaml file -

i trying encode following string, want use regex requirement within yaml file. keep getting error "the yaml values not appear valid utf-8"

parameters:   user_reg:      "[a-za-z0-9\s'\-$&_*+#!?§]+" 

i tried following, still getting same error:

parameters:   user_reg:      "[a-za-z0-9\s'\-$&_*+#!?§]+" 

whats correct utf-8 term expression?

use first expression, ensure file encoded utf-8. can check (and change) using example notepad++.