I am looking to learn the alto trombone, but my problem is, I need to find a alto trombone on a budget of around $1000...I'm really looking for a good used one with a trigger (something that I can take with my through college (for trombone choir, orchestra, and solos)- But I have a few songs I could use it on very well right now)
I've heard and read reviews about, probably the cheapest alto, the Chinese Selman Alto trombone...I know that wouldn't be a horn I'd take through college, but does anyone know anything about these? Most review I've read liked them for the money.

The word on the selman altos is that if you get a slide job on them and change the leadpipe, you've got a fairly decent horn.
If you were looking for a straight alto, your budget would do you just fine, but It's going to be hard finding one with a valve for that price range.

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By the way, do you absolutely have to have the valve? It does facilitate some trills, but plenty of players get by just fine without one.