Keeping coins away from your little brother—or sister—is a good idea.
But storing them outside in a tree house isn't.
Sharp changes in temperature and moisture can cause tarnish and spots.
You'll want a ruler to measure your coins, but it should be made of plastic.
A metal ruler can scratch your coins!
While some plastic flips are okay, you want to avoid the soft ones.
The PVC that makes the plastic soft also causes green slime.
A computer can help you keep track of your collection.
But using a spreadsheet program to add up denominations isn't that useful.
You'd be better off with a coin program that lets you store notes about your collection.