I'd say that, at $550-per, you can't go wrong. Unless they're really "beaters" (and a guy who has 3 is probably more a collector than a beater-type), you can always get more than you paid for them. And I think you'll find they're really nice guns. As you note, they're tricky to take apart (that's discussed elsewhere on ythis forum); but, as Graybeard says, you probably won't have much need to ... they're pretty straightforward to clean and care for without any disassembly. Of course there were 2 types made: with medium-heavy round barrel and octagon; and various calibers. I don't know that any were especially "rare", although the 45-70s (with iron sights) were apparently the most common. Personally, I'd think the 25-06 would be really neat ... but that's just me (I wouldn't mind a 30-06 either). There's a couple of guys on GunsAmerica who deal in B-78s ... some used and some NIB; they're notoriously over-priced, but their's are all priced between $1200 and $1500. Other individual sellers seem to price their's from $800 on-up. Sounds like a nice opportunity to me.