Is there a way to prove that a key is legit and works before buying it? Otherwise, people will trust established sites like g2a to get cheaper keys. Personally I have never bought keys outside of Steam itself because im too paranoid to trust anyone. Keys that don't work, or are obtained illegally, are a common case amongst resellers (im not saying you aren't legit, just saying).
Yep.. Also you could have your previous customers whom you were able to work with. That way we could actually see if this is for real.