My grand-mother got her old guitar out of her closet and started to play again. She brought it to a repair shop for a check-up and the guy there told her that her guitar was worth 800$-1000$ and that the damages on the guitar (wich are minors) could cost her 300$.
I'm wondering if he's right or ifmy grandma just went to the wrong store where dishonnest jerks takes advantage of old ladies.
I've made some research on the internet but I found nothing about the value of the guitar now. I found out it was the copy of the Gibson J-200 (wich is sold between 2400$ and 3000$ on ebay).
My grand-mother purchased it around 1972 and remembers paying it 300$ although I found a guy on the internet who payed 200$ for a similar guitar in 1978.
Could someone help me make my grandma happy?

El Degas
Modelo GB 84
Serie no 2
Bought around 1972, maybe 1973
Thanks !