$150 for 10 yards is expensive in this neighborhood. Going price right now is $90 to $100 for an 18 yard dumptruck. Everywhere is different, so shop around a little, at least for a bigger truckload. You would be surprised at how far an 18 yard dumptruck load of dirt WON't GO! It seems like a lot if your shoveling it, but if your filling holes, it goes away fast.
Like others already posted, I agree with getting the mulch out of the hole as best you can. I came home years ago and my Father in law was raking the chips back into the hole on a stump that was right on the edge of my driveway (dirt drive). I got into an arguement with him about it, him saying it would be ok, and me knowing better. Wife got onto me for argueing with him over it, saying he was just trying to help. I left it alone, and to this day I have something to remind me of him, a soft spot in the edge of my driveway. (I have other better things to remind me of him also, so don't take that wrong)
David from jax