I offer custom length necklaces for most chains, contact me for details. If you'd like any quantity of any item, 1 to 1000, or whatever you need, contact me. I am happy to make any listing you'd like. If you are looking for something, let me know, I can usually find it for you.
The best thing you can do with sterling silver and gold filled jewelry is keep it sealed in a baggie when you aren't wearing it, to prevent oxidization. It is also best to keep it from chemicals, sweat and grime. There are jewelry cleaners, that if used occasionally, can really help keep the product clean.