Well first of all I wouldn't recommend any boost over 6 lbs on stock internals.
I would definitely ask what you're getting in the kit for that price! (it better be everything). We have a intercooled Procharger kit for $4995 (5-6lbs) and for the month of March we are including a fuel pump and injectors at no additional cost.
If we install and tune it here locally in Las Vegas we charge $900...
Food for thought,
b or w bodys?