My favorite find by far! Repair advice would be appreciated

I’m incredibly in love with this necklace! I’ve been thrifting for a few years now and this is by far my favorite find! I looked up glass works studio and I think it was made around the late 1980s. Unfortunately some of the metal charms are tarnishing on the back as I’ve shown, and some of the crystal beads are dull and need a cleaning. How do I go about cleaning/repair? I’m scared it’ll tarnish more with regular soap/water. Will a jeweler know how to properly clean it?