What Criteria/Rules do you have for yourself when it comes to collecting?

Do you have any rules you set for yourself when it comes to your collection? I feel like we all have rules for ourselves as collectors, whether it's for budget reasons, your preference of where you buy your anime, what format you prefer. I'm just curious to see what everyone's criteria are.

Here's my criteria/rules:

• Don't buy the DVD version of a title, unless the Blu-ray and 4K are super expensive and rare, or it's a title exclusively on DVD, i.e. Trigun, Beck Mongolian Chop Squad, Black Cat.
• Don't get collector's editions and/or steelbooks unless it has exclusive bonus features or the price is lower than the standard edition (Hot take, but I only care about the contents on the disc, I don't care for the physical items that usually come with collectors editions).
• Don't spend more than $50 on a single product, wait for it to go on sale. Unless it has enough content on the discs to justify the $50+ price point (25+ episodes and/or a collection of movies).
• Use the Crunchyroll Store least as possible (Only for Aniplex titles or Exclusives)
• Only buy second hand for OOP titles, or if the title is still in print and the ebay price is really worth it and has the slipcover.