I've recently been thinking of buying a bass trombone. Does anybody know how much a decent used one might cost?

It depends on what you're looking for, but I'd say expect to spend at minimum 1500 dollars. Sweet deals can be found on ebay, but so can cons, so be careful. (For what it's worth, I found a steal on mine.. woo hoo!)
Have you narrowed down what you're looking for? Single rotor or double? Dependent or Independent?
Check the Trombone Forum Classifieds.. a lot of good horns come up for sale there.

hi, i'm new here, and i'm a 15 year old guy(tenth grade) who really wants a Bass Trombone for jazz band, symphonic band, maybe a quartet or a quintet, and my last year of marching band(i don't want to risk it getting dented right when i get it), and i just wanted some input on what type of Bass Trombone i should get. i really want a nice double independent rotor system but the cheapest i can find is 2,750. my parents are paying for 1,000 of it and i pay the rest. i'll owe them because i don't have enough money to buy it myself right now. but back on topic, i want either a king/conn, or a yamaha. any suggestions on what i should get?

This is a Benge 290 on eBay. No one has bid yet (as of july 8, 2008 12:25AM central time) and the starting bid is at $995, and it has about two days left on the auction. These horns are good and are very similar to the king bass trombones.

http://cgi.ebay.com/Benge-290-Bass-Trombone_W0QQitemZ160257262636QQihZ006QQcategoryZ16216QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

-Raul

thanks, i'll let you know if my parents agree.

Heck, if they don't agree, I might just throw a bid on it. If it goes for anywhere near that price, it'd be a steal.

they're really thinking about it.

About 21 hours left on that bad boy. NO BIDS YET. ends at 5:00 AM central time.

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I have seen one of these go for about $1800. Benge has always been seriously underrated. I know I have seen different videos of the Kenton band in the 60s and 70s with a few different trombone players on the Benge 190F open-wrap tenor bone.

GOOD LUCK, if I wasn't waiting on a $900 check for another King 4B I sold a week ago, I would buy this bad boy too, Steve.

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WOOPS. totally miscalculated the ending time for that Bass Bone. ends early this evening.

Hello,
I have just bought one bass Vincent Bach Stradivarius 50BLG 2 rotors Hagmann. Paid (in francs Swiss) 9160.-

Magnificent trombone!

I can understand the single and double rotor, but what's "dependant" and "independant"? I'm just curious. I'm not going to be very picky about one I get because it's just going to be something to have fun with on my own.

On a "dependent" horn, the second valve will only operate when the first valve is engaged. On an independent horn, the second valve will work regardless of the first. This opens up some interesting new slide/valve combinations. I play a dependent system and have never felt like I was missing out. Your mileage may vary.