PSA grading- Determining value and invoices with Balance due?

camlov2

I have just started sending in cards for grading and have determined that I am not very good at estimating grades.
I have gotten some cards back two grades higher than I thought, as well as cards that are multiple grades lower (I normally missed something wrong with the card).
After each submission returns I get an email which states the cost of the submission and amount paid and ends with a zero balance.

My question is- Has anyone ever got something other than a zero balance?

or phrased another way- Has anyone ever undervalued a card so much that the company says you didn't sent enough money for the grading?

For example- I just got back a lot of cards from a Monthly special, all cards are supposed to be $100 or less. I had a card I estimated a grade of 7 which gives me a value of $75. The card actually graded a 9 (tied for top pop) and has a value of $500.

jdduck

jdduck

I have sent in over 100 submissions / 6000 cards under the monthly specials over the last 8 years. Up until this summer, I have never been charged extra after the grades. This summer, I did get overcharged for about a dozen or so cards that graded higher than expected, which increased the value over to the maximum value of 100.00 per card. You can search for my earlier post named:
Collectors Club Submission Fee Increase due to actual grade