This is a Bach TB301 trombone in excellent condition. I have included links below to sales of similar instruments to give you an idea of the market. Please let me know if I can be of further assistance.

Serial number 525907, 2006:
https://www.bachloyalist.com/serial-numbers-trombone/

About TB301:
https://www.bachbrass.com/instruments/trombones/tb301

Price guide at bottom:
$100-$700
https://reverb.com/p/bach-tb301-student-model-tenor-trombone

Asking:

$416, ‘good’
https://reverb.com/item/36066035-bach-361847-tb301-trombone

$499, ‘very good condition’
https://bit.ly/3zQKqfo

$550, excellent
https://reverb.com/item/35729771-bach-tb301-student-trombone

$785, ‘very good’
https://bit.ly/3ffmAC4

$1223, ‘mint’
https://reverb.com/item/16040896-bach-tb301-student-trombone-standard-finish

$1374, condition unclear
https://reverb.com/item/30187315-bach-tb301-student-8-inch-bell-trombone

New, $1399
https://reverb.com/p/bach-tb301-student-model-tenor-trombone

Hammer:

$102
https://www.ebay.com/itm/234007725509?hash=item367bf285c5:g:rD8AAOSwjBVgnVa1

$239
https://www.ebay.com/itm/233672277114?hash=item3667f3fc7a:g:dQkAAOSwNNxfLC76

$259
https://www.ebay.com/itm/203182557011?hash=item2f4e9fc753:g:Q98AAOSw-IRfsb0~

$269
https://www.ebay.com/itm/133747957446?hash=item1f23ffdec6:g:RZQAAOSwwpRgjgSx

$325, ‘great’
https://www.ebay.com/itm/274607229364?hash=item3fefddc9b4:g:4hkAAOSwcbpf0QZj