If you know the luthier doing the work to be a good one, don't worry about it. Repaired properly, a crack is no problem, in fact with some woods they are to be expected. Cedar, for example, is known to crack. I would probably negotiate a discount and buy it anyway, once I have examined it.

I am curious as to the brand of the bouzouki. I have a Freshwater, and love its tone and playability.

Mick