The problem is when comparing one information with the another how much one unit would cost there are diffrent costs.
The point is often such reports wich are reffering to dealings don't provide often and reliable sources about what kind of deal and its transfers it's inclueding, like extra parts,engines,teaching personal,personal to teach maintenance for foreign mechanics, and so on.
Also i don't believe that Attack Helicopters have a standard price per unit for every willing buyer.Since it's a question about buisness i think the Unit costs can variate from customer to customer.
Not all cows giving exactly 2 liters milk, others give more so i think they will be milked when they could manage this.
So the question is about the Unit costs for the developing country wich should have a moderate prize per unit.
So here is the question to the community wich maybe has more reliable sources about the actual costs per Unit for all Attack Helicopters you could know.
I mean there are sources wich claim that Mi-28N costs about 8 Mln USD per unit and other claims it costs 45 Mln USD (not ruble).