Rather than challenging your opponent directly, the game plan is to get more value from your board than your opponent can from theirs, faster - while also using tricks to disrupt them and Bodyguards to protect your more important characters
It's arguably the most famous Five Color card ever printed
Some collectors even avoid placing their most prized cards on the very first or last page of a ring binder as an extra safety measure
To be clear, I'm not against stores (especially smaller independent businesses) increasing prices a bit on things that are in super high demand, especially if they provide a service to customers like the ability to reserve items or make pre-orders (though simply taking a deposit would be ideal)
Or, at least, thats its not that bad
Avoid including too many different types of Pokemon or Trainer cards, as this can lead to inconsistency in gameplay