Can you define if it's coming from the front or rear?
The list of possibilities is long. If you're not a DIY guy, I would recommend taking it to another shop or dealership. Or competent mechanic you go to. You need to ask them to put one of their better guys on it, not a less experienced tech. Go over it with a fine toothed comb. It might be something like a shield or exh pipe rattling too. Shops usually do a suspension diagnosis for free, but if it's an especially comprehensive inspection, it might be worth paying a fee.
I might be inclined to take it to two other shops and see if there is concensus. This is one of those things where a guy might see something and stop there ...and you could end up replacing several items over multiple visits till you finally get to the bottom of it. Best to find the root-cause first and not throw parts at it.
Potential things (no particular order):
1) Loose brake caliper
2) Worn ball joints or steering joint
3) Worn bushing/s (shocks or A-arm)
4) Loose shield
5) Loose inner fender panel
6) Loose or cracked exhaust hanger
7) Loose wheel center cap
8) Rear suspension issues (joints/bushings/etc).
9) Engine mount
10) Emergency brake cable rattling
11) Steering shaft binding (releasing "Pop!")
12) Power Steering Rack/bushing/bolt (loose)
13) CV shaft (loose/worn)
14) Wheel bearing (loose/worn)
15) Tailgate
16) Body mount
17) Stuck/sticking brake pad (rusted sleeves)
.