Humidor value....Help please

[mannish]

My sister-in-law was asking me about my brothers Partagas humidor and was it worth selling. I said YES. It's one of the those nice Partagas Limited Edition 150 that has all the drawers course the cigars are gone.
I don't know the model it's big with lots of drawers my brother won it and he said it was am expensive humidor..?

So where would I start in finding what this sell for. Thanks