IGN: Describe I will buy your spawners at 4 diamonds. If you sell me 10 spawners, I'll buy it for 5 diamonds each, so you would get 50 diamonds for 10 spawners. If you sell less than 10, I'll buy it at 4 diamonds each. Please let me know if you'd be interested in selling your spawners to me.
I'd agree with jim. Spawners are nearly impossible to get at 4 or even 5 diamonds each. You'd have to offer up to 6 diamonds to actually get a deal.