I would say if it's in excellent condition, it's a decent deal. It would be a better deal if you could talk him down a little.
I bought a nice used one recently for a little less than 200.00,
I find it to be a good coin shooter. It's a 4 filter detector so you will have to swing it fairly briskly to get the depth it's capable of. I acquired a 6" coil for it and thats what I use mainly as I like smaller coils. Pretty easy to set up as all you need to tweek is few settings like threshold volume and sensitivity. It's a bear on batteries, so I recommend you get some good rechargeables Not a huge menu like the spectrum eagle.
Heres a picture of silver I found first time out with it.
Good Luck with it , if you decide to pull the trigger on it.
HH, Tico