A few hundred to tens of thousands depending on what you want done.
$25
25 USD and up. you dont buy it you just keep walking and youll find it
You will have to describe it in more detail.
That is an extremely vague question. A .357 can run from a couple of hundred dollars to several thousand depending on what it is.
As little as $15 and as much as $1,500 or more, depending on what you want.