First thing I would do is do a visual inspection of the serpetine belt to make sure its condition looks good. If you see small cracks, fraying around the edges then that should be replaced regardless of whether or not it is the actual culprit of the noise.

Take off the serpertine belt and spin each of the pulleys including the tensioner. If any of them feel rough / hard to turn / scratchy then that may be your problem.

After that then I would start digging deeper into the engine bay and see if it's something else causing the problem. I would look into the timing belt region to see if there are any failing components there such as the water pump, tensioner, and idler pulley.

These cars aren't really easy to work on when you're first starting out with them. If you're not able to do the work yourself and want to avoid a dealer I would recommend finding a good shop that focuses on German vehicles. They typically run around $75-$85 an hour (At least around where I live) so it's not a whole lot better than the dealer, but it's still cheaper.

 

I fixed the vacuum leak and the check engine light went off. Phew, fixed that.

The sound really seems like its something that is spinning in the front. Either the belt or the fan. The water pump I know is supposed to be changed very soon. Would the water pump be making a clicking noise in the front?

 

Water pumps are normally changed when the timing belt work is done. The OP stated he had 130k on the vehicle and the only work done was the MAF sensor. If the timing belt was never done, then it's time plus all the tensioners, water pump, belt, etc.