My nephew just began playing trumpet. He was given an old yamaha ytr 2320. So, now that he has his very own instrument we were trying to find out some info on its history. Is there a way to date the instrument through serial number? Also are there any interesting facts regarding this model?
As you can tell I know nothing about them, so any input would be appreciated!

The YTR 2320 was manufactured by Yamaha between the years of 1984 and 1997. It's predecessor was the YTR 232 (made from 1969 thru 1983), both have the same basic deminsions. It is in the standard key of Bb. The bore of the instrument is .460 inches. The bell should be 5 inches across. And it is considered to be 'light'. The replacement after 1997 is the YTR 2335.

If the springs are weak and felts overly worn you can easily get a rebuild kit for $30. It might be better to have the local repair shop do it though so check with them first, they might have a brand of kit they prefer to work with.

You can find a Yamaha YTR-2320 for about $100-$200 on auction sales.

This might give you some ideas about its value.
http://trumpetsearch.com/trumpets-by-brand/yamaha