It is usually about 40 to 50 cents per lb of hanging carcass weight. However this can vary widely depending on what sort of inspection you need (for your own use or for sale in state or across state lines), what sort of wrapping and extra services you use (pre made hamburger patties, trimmed stew meat, etc).
USDA inspection with cryovac packaging and patties can total about $1/lb of carcass weight. For your own use, 45 cents + about a $40-50. kill charge should cover it. Jim