Generally speaking, the Conn 15J Bb tuba can range in price from around $1,500 to $3,000 USD, depending on the tuba's condition. This wide price range largely reflects the tuba's age and condition, as older and heavily-used tubas may require more extensive repairs or parts replacement.
* Excellent Condition: A Conn 15J in excellent condition, typically with minimal signs of wear or damage, can fetch prices at the higher end of the scale, usually between $2,500 to $3,000.
* Good Condition: A Conn 15J in good condition, with some minor wear but still fully playable, may sell for around $1,500 to $2,500.
* Fair Condition: For a Conn 15J in fair condition, with more noticeable wear and blemishes but remains functional, the price can range between $1,000 to $1,500.
* Poor Condition: Conn 15Js in poor condition, perhaps with significant damage or missing parts, may be sold for as low as several hundred dollars.
Since you mentioned the tuba is in "pretty worn condition," it's likely to fall somewhere in the fair or poor condition range. Therefore, a reasonable price for this particular tuba could be around $500 to $1,000, assuming it's still playable.
It's important to note that these prices may vary depending on the local market and the specific buyer or seller. Also, condition assessment is subjective, so getting multiple opinions or having a qualified instrument technician inspect the tuba can help ensure a fair price for both the buyer and seller.