Cost estimation full re-caulking aluminium roof (16 feet tt)

Okay, if I decide to remove all the old caulk and start "from scratch", how do I deal with the kind of metal moulding which is screwed on the edges of each side? What's that exactly? It's like a moulding that hold the aluminum cover in place? How do I deal with that? Do I need to remove it completely or I just remove the caulk above the moulding without removing it? Does it have a seal underneath or is it just caulk? If I completely remove the moulding, how do I reinstall and reseal it thereafter?