A very different formula to those already posted, used with great success by some people, is
price = whatever you think the customer is willing to pay at most
Obviously, this formula contains a variable that is hard to determine, but I've seen cases where a customer was willing to pay €800 for a task that hardly takes an hour to complete. And similar differences on a larger scale. The task is very important for the customer, because it makes or saves him a lot of money, so he is willing to pay a lot, without considering how much it takes to do it.
So imagine you were the business team, and your really needed those reports a.s.a.p., how much would you be willing to pay instead of looking for someone to make it cheaper? Maybe they have a budget of USD10K for those reports, so why should you make it for USD2K?
You should do the other calculation, price=rate*expected hours*uncertainty factor+expenses, too; if this results in a higher price, you should reconsider doing the job at all.