From my brief research on walkthrough tier (looking at CGC board posts from 2020-2021), I was under the impression that CGC uses the declared FMV when charging the 3% fee, and charges more if it ends up being undervalued but does not refund anything if it ends up being overvalued. I would definitely love to submit it walkthrough if the fee is calculated after being graded, as that would give me peace of mind that I won't end up paying a ~$500 fee for a $2,000 9.6 - can anyone that has used walkthrough chime in on how the fee calculation works exactly (when it's charged and over/under declaring)?
I have submitted a 300 before (that was direct edition) via modern tier and it was rightfully bumped up to Express after being graded, but this is my first time potentially interacting with the walkthrough tier.
Thank you all for your input!