In practice, we suggest that any "investment" outside of the Reserved List should be viewed with a 2-3 year exit strategy in mind
There are also Special Energy cards, like the popular Double Colorless Energy, but each Special Energy is restricted to 4 per deck, as opposed to an open-ended number of Basic Energy
Take pictures from both sides
Build strong relationships with your Local Game Store (LGS), track the exact weekly restock morning patterns of local retail stores, follow online notification communities like the r/PokemonTCGDeals subreddit, and practice patience when high-demand sets undergo inevitable factory reprints
One of the challenges of building an equipment deck is that you need equipment, but also creatures to equip, because without a creature in play, equipment doesn't do all that much