You really need to check out what size you are...(you should be 4/4)....
If this violin is valuable, you may want to check with specialist about it's condition and it's essential value.
If you are wanting to play it, then you will need to probably make some adjustments to the strings and such.
If it is about 300 years old...then you should get a Really good price..(i'd say 5,000)???
depending on the brand of course..and you aren't be too detailing about that..
tell me what happens if you check...i'm curious....