The regex solution would look like this
^(?:10000|(?:(?:(?:2[5-9]\d)|[3-9]\d{2}|\d{4})(?:[,.]\d{2})?))€?$
See here online on Regexr
But it would be better for checking if a value belongs to a range, not to use a regex. You can extract the value easily and do a normal <> check on numbers outside.