It's kinda hard to say. Bach 42's can be a crap shoot. Are you going to be able to play it first? I've played some really nice Bachs and some real duds. If you're not in a position to try it out first, I'd try to get the price down. For me personally, I wouldn't need all the stuff he's selling with it. If you do, maybe it's worth it.
Also, with any horn, always assume it will need a slide job, and be pleasantly surprised if it doesn't.
If it's a local deal, try it out. If the horn is a player, sure, I'd spend the money. But the former car salesman in me would try to work the price down