Black Horse Acoustic - any value?

Hello everyone,

My wife has an acoustic guitar that here mother bought here when she was about 12 years old ... so it is now about 28 years old (don't do the math!). It has been stored in our cupboards ever since I met my wife, and she is now looking to sell it. It is a Black Horse model numer SG-225. It looks like a smaller size guitar, but I do not see any discernable detail other than the label inside. I have no knowledge of guitars, neither does my wife, so we are a little lost at the moment. Does this guitar have any value?

Thanks for your time!

Here are some photos I have taken: