You have only provided a generic description. Trying to put a value on anything with just this limited information provided is difficult. Value depends on a combination of many factors. Without a detailed description to include, finish, barrel length, overall condition, gauge, stock material, sights, box, original paperwork and any accessories, only a general estimate can be given. This weapon could be in the 100-450 USD price range.
50-360 USD or so
A shotgun.
S&W never made a Model 1300 XTR shotgun.
A shotgun made for Smith and Wesson, sold under the Smith and Wesson name.
No such model number.
20-100 USD a box
No such model number
$650-$1000 used
Standard Catalog of Smith and Wesson, 3rd, ed., by Supica and Nahas can answer your question.
500$
Depends on the store.
50-350 usd