Hi guys, a little help would be great!

I've got a 2006 1.6 VW Golf FSI petrol.

The MOT is due soon, and unfortunately, the exhaust is blowing. I can hear it coming from the underside of my car, I just can't pinpoint where. I'm scared shitless that it'll cause an MOT fail and don't want to take it to a garage to potentially get ripped off over getting it fixed, as I have no idea if the pipes just need welding, or if the back box needs replacement.

Is this a common issue with this model, or can anyone suggest me where to start with getting it sorted? Many thanks for help in advance!