value of longines presence watch?

[claw1234]

:?  can anybody help me value a watch i've picked up along the way.....it's a longines presence gents watch with a diamond patterned face and gold surround....it is approx 8 years old and unfortunately is engraved on the stainless steel back...i am going to sell it and want to make sure i'm not getting ripped off...can anyone help with either more info or an approx value?    thanks .....chris