Your title asks about Facebook targeting but the text asks about hosting, so a few people answered different questions. Clarify which one you want and you will get better advice. On the targeting side, I agree with what gimabor said about judging by conversions, not clicks. A simple way to test it: run broad and one interest audience side by side with the same budget and the same ad, let both run for several days before deciding, and compare cost per lead or sale. Cheap clicks that never convert are the usual trap. Exclude your existing customers and recent visitors so you are not paying to reach people who already know you.
