If you are planning to use Nature - Cide Pest Management X2 to treat other peoples homes to earn a profit, yes you need to have an applicators license. If you are using this product for your own property then you don't have to have one.
Nature - Cide Pest Management X2 should be applied when no rain is expected within 24 hrs of the application. Applying during rain or if rain occurs shortly after the application, results would not be effective. Please view the full product label for more information.
Nature - Cide Pest Management X2 is not labeled for carpenter bees/bees. If you are looking for something more natural, you may consider using EcoVia EC