I'm a little confused, "So i was givin a rolay angel they said they only paid 30 because of," so you're not having to pay anything for the angel, the person who paid $30, give you the angel for free? Or you're paying $30 for him? Private or Business? If it's private, I'm a bit appalled that the person won't give you the fish for free with the hope of best intentions for the fish. If it was a business, that's not any better, as they still made a profit selling a sick fish, as I'd be willing to bet they paid less then $30 wholesale for the angel, depending on size/origin.
All that said, a healthy and eating Royal, or Regal Angel, is definitely worth more then $30, so it could be an investment. A large Red Sea Regal, (aka Yellow-Bellied Regal), is definitely worth north of $100. However, I will say that most Regals don't eat in aquariums and most unfortunately perish. Takes a skilled hand raising one.