One way I usually deal with this problem is by saving sellers on eBay that not only post the card, but immediately tell you the condition, or have multiple options of the same cards and list what they think each card condition is

Mint The Spot, Living Portal #153 Magic Marvel Spider-Man Price$3.39 Mint Swamp #196 Magic Marvel Spider-Man Price$1.69 Mint Spider-Man India #151 Magic Marvel Spider-Man Price$2.19 Mint Electro's Bolt #77 Magic Marvel Spider-Man Price$1.59 Mint Prowler, Clawed Thief #138 Magic Marvel Spider-Man Price$1.49 Mint Starling, Aerial Ally [Foil] #18 Magic Marvel Spider-Man Price$1.99 Mint Spider-UK #17 Magic Marvel Spider-Man Price$1.59 Mint Spider-Rex, Daring Dino #116 Magic Marvel Spider-Man Price$1.79 Mint Daily Bugle Reporters #6 Magic Marvel Spider-Man Price$1.59 Mint Spider-Islanders #91 Magic Marvel Spider-Man Price$1.59 Mint Passenger Ferry #170 Magic Marvel Spider-Man Price$1.59 Mint Lurking Lizards #107 Magic Marvel Spider-Man Price$1.59 Mint Skyward Spider #146 Magic Marvel Spider-Man Price$1.59 Mint Robotics Mastery #41 Magic Marvel Spider-Man Price$1.79 Mint Island #190 Magic Marvel Spider-Man Price$1.79 Mint Spider-Ham, Peter Porker #114 Magic Marvel Spider-Man Price$2.49 Mint Venomized Cat #72 Magic Marvel Spider-Man Price$1.79 Mint Hot Dog Cart #164 Magic Marvel Spider-Man Price$1.69 Mint Web-Shooters #22 Magic Marvel Spider-Man Price$1.59 Mint Common Crook #53 Magic Marvel Spider-Man Price$1.59

Illustrated by: Ron Spencer Rulings 2005-10-01 The tokens and counters that Doubling Season creates are exact copies of the kind of tokens and counters that were being created in the first place
Burn, Group Slug, and Combo
Pokmon Korean cards are produced in larger quantities and have lower distribution costs, making them more affordable
Some cards care about having small creatures, but they can still add up fast