Seems like it would be quite a lot of years old, why can't you use it for your leisure rides? Can't you tweak the fit at all? What amount of money would you spend on a leisure bike? If you google, you can probably get an idea of sold bikes. There is no current value for used stuff, it is just what you can get for it, right, your 300 miles means very little. Bike shops like car dealerships will buy low because they have to resell.