Well, I can talk about the price because it depends on the following factors:
1) Model size
2) Skeleton complexity
3) How accurately the skinning was imported
4) And how much time it will take to make the model look perfect without any flaws.
Also, it's important to consider that there are models whose skeletons differ in almost every possible way, for example, the angels from Heroes 6 and 7 have such a significant difference that I wouldn't even take on those projects for money.
But still. If we're just estimating, not giving an exact number, but a very rough estimate.
How much would you want for adapting that footman model? From start to finish, i.e., the final result is a working model in the game. And how long would it take, roughly?
By the way, I looked at this model before, so I have a general idea of what it's like and how challenging this task is.