Just going to repeat this again regarding getting the quality pass from Lin Lin since people are having so much trouble
Oh, nice too know. Then that's the quality pass seed you need to make your own quality pass counterfeits in the workshop.
I was expecting that the player would be copying Fawn's pass or something.
Basically, once you get the Quality Counterfeit Pass from the guy Lin Lin recommends you to, you then buy pens at the hardware store (like 20 of them; they're cheap), and then you buy extra shabby/rough/wrinkled/gnarled counterfeit passes from the slums market. afaik it doesn't matter which of the four low quality counterfeit passes you buy.
Then you go into the workshop (There's workshop stations in your apartment, Cassie's hideout, and some other areas), and you combine the pen with one of the low quality counterfeit passes. If you didn't have the Quality Counterfeit Pass, it would give you a message saying that you'd need a better pass to copy from (this was the hint). Since you do have the Quality Counterfeit Pass, combining the low quality counterfeit pass and the pen gives you a Nimble skill check to "Attempt improvements". Higher your nimble skill, better chance of success (I have Nimble Lv 13, and my success chance is 54%). Succeed, and the low quality counterfeit pass and pen are lost, and you gain a Quality Counterfeit Pass. Hence, buying the first Quality Counterfeit Pass for $500 is to buy it as a seed pass for you to make copies from.